path: root/libhb/common.c

/* $Id: common.c,v 1.15 2005/03/17 19:22:47 titer Exp $

   This file is part of the HandBrake source code.
   Homepage: <http://handbrake.fr/>.
   It may be used under the terms of the GNU General Public License. */

#include <stdarg.h>
#include <time.h>
#include <ctype.h>
#include <sys/time.h>

#include "common.h"
#include "lang.h"
#include "hb.h"

/**********************************************************************
 * Global variables
 *********************************************************************/
hb_rate_t hb_video_rates[] =
{ { "5",  5400000 }, { "10",     2700000 }, { "12", 2250000 },
  { "15", 1800000 }, { "23.976", 1126125 }, { "24", 1125000 },
  { "25", 1080000 }, { "29.97",  900900  } };
int hb_video_rates_count = sizeof( hb_video_rates ) /
                           sizeof( hb_rate_t );

hb_rate_t hb_audio_rates[] =
{ { "22.05", 22050 }, { "24", 24000 }, { "32", 32000 },
  { "44.1",  44100 }, { "48", 48000 } };
int hb_audio_rates_count   = sizeof( hb_audio_rates ) /
                             sizeof( hb_rate_t );
int hb_audio_rates_default = 3; /* 44100 Hz */

hb_rate_t hb_audio_bitrates[] =
{ {  "32",  32 }, {  "40",  40 }, {  "48",  48 }, {  "56",  56 },
  {  "64",  64 }, {  "80",  80 }, {  "96",  96 }, { "112", 112 },
  { "128", 128 }, { "160", 160 }, { "192", 192 }, { "224", 224 },
  { "256", 256 }, { "320", 320 }, { "384", 384 }, { "448", 448 },
  { "512", 512 }, { "576", 576 }, { "640", 640 }, { "768", 768 } };
int hb_audio_bitrates_count = sizeof( hb_audio_bitrates ) /
                              sizeof( hb_rate_t );

static hb_error_handler_t *error_handler = NULL;

hb_mixdown_t hb_audio_mixdowns[] =
{ { "None",               "HB_AMIXDOWN_NONE",      "none",   HB_AMIXDOWN_NONE      },
  { "Mono",               "HB_AMIXDOWN_MONO",      "mono",   HB_AMIXDOWN_MONO      },
  { "Stereo",             "HB_AMIXDOWN_STEREO",    "stereo", HB_AMIXDOWN_STEREO    },
  { "Dolby Surround",     "HB_AMIXDOWN_DOLBY",     "dpl1",   HB_AMIXDOWN_DOLBY     },
  { "Dolby Pro Logic II", "HB_AMIXDOWN_DOLBYPLII", "dpl2",   HB_AMIXDOWN_DOLBYPLII },
  { "6-channel discrete", "HB_AMIXDOWN_6CH",       "6ch",    HB_AMIXDOWN_6CH       } };
int hb_audio_mixdowns_count = sizeof( hb_audio_mixdowns ) /
                              sizeof( hb_mixdown_t );

hb_encoder_t hb_video_encoders[] =
{ { "H.264 (x264)",       "x264",       HB_VCODEC_X264,         HB_MUX_MP4|HB_MUX_MKV },
  { "MPEG-4 (FFmpeg)",    "ffmpeg4",    HB_VCODEC_FFMPEG_MPEG4, HB_MUX_MP4|HB_MUX_MKV },
  { "MPEG-2 (FFmpeg)",    "ffmpeg2",    HB_VCODEC_FFMPEG_MPEG2, HB_MUX_MP4|HB_MUX_MKV },
  { "VP3 (Theora)",       "theora",     HB_VCODEC_THEORA,                  HB_MUX_MKV } };
int hb_video_encoders_count = sizeof( hb_video_encoders ) /
                              sizeof( hb_encoder_t );

hb_encoder_t hb_audio_encoders[] =
{
#ifdef __APPLE__
  { "AAC (CoreAudio)",    "ca_aac",     HB_ACODEC_CA_AAC,       HB_MUX_MP4|HB_MUX_MKV },
  { "HE-AAC (CoreAudio)", "ca_haac",    HB_ACODEC_CA_HAAC,      HB_MUX_MP4|HB_MUX_MKV },
#endif
  { "AAC (faac)",         "faac",       HB_ACODEC_FAAC,         HB_MUX_MP4|HB_MUX_MKV },
  { "AAC (ffmpeg)",       "ffaac",      HB_ACODEC_FFAAC,        HB_MUX_MP4|HB_MUX_MKV },
  { "AAC Passthru",       "copy:aac",   HB_ACODEC_AAC_PASS,     HB_MUX_MP4|HB_MUX_MKV },
  { "AC3 (ffmpeg)",       "ffac3",      HB_ACODEC_AC3,          HB_MUX_MP4|HB_MUX_MKV },
  { "AC3 Passthru",       "copy:ac3",   HB_ACODEC_AC3_PASS,     HB_MUX_MP4|HB_MUX_MKV },
  { "DTS Passthru",       "copy:dts",   HB_ACODEC_DCA_PASS,     HB_MUX_MP4|HB_MUX_MKV },
  { "DTS-HD Passthru",    "copy:dtshd", HB_ACODEC_DCA_HD_PASS,  HB_MUX_MP4|HB_MUX_MKV },
  { "MP3 (lame)",         "lame",       HB_ACODEC_LAME,         HB_MUX_MP4|HB_MUX_MKV },
  { "MP3 Passthru",       "copy:mp3",   HB_ACODEC_MP3_PASS,     HB_MUX_MP4|HB_MUX_MKV },
  { "Vorbis (vorbis)",    "vorbis",     HB_ACODEC_VORBIS,                  HB_MUX_MKV },
  { "FLAC (ffmpeg)",      "ffflac",     HB_ACODEC_FFFLAC,                  HB_MUX_MKV },
  { "Auto Passthru",      "copy",       HB_ACODEC_AUTO_PASS,    HB_MUX_MP4|HB_MUX_MKV } };
int hb_audio_encoders_count = sizeof( hb_audio_encoders ) /
                              sizeof( hb_encoder_t );

/* Expose values for PInvoke */
hb_rate_t* hb_get_video_rates() { return hb_video_rates; }
int hb_get_video_rates_count() { return hb_video_rates_count; }
hb_rate_t* hb_get_audio_rates() { return hb_audio_rates; }
int hb_get_audio_rates_count() { return hb_audio_rates_count; }
int hb_get_audio_rates_default() { return hb_audio_rates_default; }
hb_rate_t* hb_get_audio_bitrates() { return hb_audio_bitrates; }
int hb_get_audio_bitrates_count() { return hb_audio_bitrates_count; }
hb_mixdown_t* hb_get_audio_mixdowns() { return hb_audio_mixdowns; }
int hb_get_audio_mixdowns_count() { return hb_audio_mixdowns_count; }
hb_encoder_t* hb_get_video_encoders() { return hb_video_encoders; }
int hb_get_video_encoders_count() { return hb_video_encoders_count; }
hb_encoder_t* hb_get_audio_encoders() { return hb_audio_encoders; }
int hb_get_audio_encoders_count() { return hb_audio_encoders_count; }

int hb_mixdown_get_mixdown_from_short_name( const char * short_name )
{
    int i;
    for (i = 0; i < hb_audio_mixdowns_count; i++)
    {
        if (strcmp(hb_audio_mixdowns[i].short_name, short_name) == 0)
        {
            return hb_audio_mixdowns[i].amixdown;
        }
    }
    return 0;
}

const char * hb_mixdown_get_short_name_from_mixdown( int amixdown )
{
    int i;
    for (i = 0; i < hb_audio_mixdowns_count; i++)
    {
        if (hb_audio_mixdowns[i].amixdown == amixdown)
        {
            return hb_audio_mixdowns[i].short_name;
        }
    }
    return "";
}

void hb_autopassthru_apply_settings( hb_job_t * job, hb_title_t * title )
{
    int i, j;
    hb_audio_t * audio;
    for( i = 0; i < hb_list_count( title->list_audio ); )
    {
        audio = hb_list_item( title->list_audio, i );
        if( audio->config.out.codec == HB_ACODEC_AUTO_PASS )
        {
            audio->config.out.codec = hb_autopassthru_get_encoder( audio->config.in.codec,
                                                                   job->acodec_copy_mask,
                                                                   job->acodec_fallback,
                                                                   job->mux );
            if( !( audio->config.out.codec & HB_ACODEC_PASS_FLAG ) &&
                !( audio->config.out.codec & HB_ACODEC_MASK ) )
            {
                hb_log( "Auto Passthru: passthru not possible and no valid fallback specified, dropping track %d",
                        audio->config.out.track );
                hb_list_rem( title->list_audio, audio );
                free( audio );
                continue;
            }
            audio->config.out.samplerate = audio->config.in.samplerate;
            if( !( audio->config.out.codec & HB_ACODEC_PASS_FLAG ) )
            {
                if( audio->config.out.codec == job->acodec_fallback )
                {
                    hb_log( "Auto Passthru: passthru not possible for track %d, using fallback",
                            audio->config.out.track );
                }
                else
                {
                    hb_log( "Auto Passthru: passthru and fallback not possible for track %d, using default encoder",
                            audio->config.out.track );
                }
                audio->config.out.mixdown = hb_get_default_mixdown( audio->config.out.codec,
                                                                    audio->config.in.channel_layout );
                audio->config.out.bitrate = hb_get_default_audio_bitrate( audio->config.out.codec,
                                                                          audio->config.out.samplerate,
                                                                          audio->config.out.mixdown );
            }
            else
            {
                for( j = 0; j < hb_audio_encoders_count; j++ )
                {
                    if( hb_audio_encoders[j].encoder == audio->config.out.codec )
                    {
                        hb_log( "Auto Passthru: using %s for track %d",
                                hb_audio_encoders[j].human_readable_name,
                                audio->config.out.track );
                        break;
                    }
                }
            }
        }
        /* Adjust output track number, in case we removed one.
         * Output tracks sadly still need to be in sequential order.
         * Note: out.track starts at 1, i starts at 0 */
        audio->config.out.track = ++i;
    }
}

int hb_autopassthru_get_encoder( int in_codec, int copy_mask, int fallback, int muxer )
{
    int i;
    int out_codec = ( copy_mask & in_codec ) | HB_ACODEC_PASS_FLAG;
    // sanitize fallback encoder and selected passthru
    // note: invalid fallbacks are caught in hb_autopassthru_apply_settings
    for( i = 0; i < hb_audio_encoders_count; i++ )
    {
        if( ( hb_audio_encoders[i].encoder == fallback ) &&
           !( hb_audio_encoders[i].muxers & muxer ) )
        {
            // fallback not possible with current muxer
            // use the default audio encoder instead
#ifndef __APPLE__
            if( muxer == HB_MUX_MKV )
                // Lame is the default for MKV
                fallback = HB_ACODEC_LAME;
            else
#endif          // Core Audio or faac
                fallback = hb_audio_encoders[0].encoder;
            break;
        }
    }
    for( i = 0; i < hb_audio_encoders_count; i++ )
    {
        if( ( hb_audio_encoders[i].encoder == out_codec ) &&
           !( hb_audio_encoders[i].muxers & muxer ) )
        {
            // selected passthru not possible with current muxer
            out_codec = fallback;
            break;
        }
    }
    if( !( out_codec & HB_ACODEC_PASS_MASK ) )
        return fallback;
    return out_codec;
}

// Given an input bitrate, find closest match in the set of allowed bitrates
int hb_find_closest_audio_bitrate(int bitrate)
{
    int ii;
    int result;

    // Check if bitrate mode was disabled
    if( bitrate <= 0 )
        return bitrate;

    // result is highest rate if none found during search.
    // rate returned will always be <= rate asked for.
    result = hb_audio_bitrates[0].rate;
    for (ii = hb_audio_bitrates_count-1; ii >= 0; ii--)
    {
        if (bitrate >= hb_audio_bitrates[ii].rate)
        {
            result = hb_audio_bitrates[ii].rate;
            break;
        }
    }
    return result;
}

// Get the bitrate low and high limits for a codec/samplerate/mixdown triplet
// The limits have been empirically determined through testing.  Max bitrates
// in table below. Numbers in parenthesis are the target bitrate chosen.
/*
Encoder     1 channel           2 channels          6 channels

faac
24kHz       86 (128)            173 (256)           460 (768)
48kHz       152 (160)           304 (320)           759 (768)

Vorbis
24kHz       97 (80)             177 (160)           527 (512)
48kHz       241 (224)           465 (448)           783 (768)

Lame
24kHz       146 (768)           138 (768)
48kHz       318 (768)           318 (768)

ffac3
24kHz       318 (320)           318 (320)           318 (320)
48kHz       636 (640)           636 (640)           636 (640)

Core Audio AAC (core audio api provides range of allowed bitrates)
24kHz       16-64               32-128              80-320
32kHz       24-96               48-192              128-448
48kHz       32-256              64-320              160-768

Core Audio HE-AAC (core audio api provides range of allowed bitrates)
32kHz       12-40               24-80               64-192
48kHz       16-40               32-80               80-192
*/

void hb_get_audio_bitrate_limits(uint32_t codec, int samplerate, int mixdown, int *low, int *high)
{
    int channels;

    channels = HB_AMIXDOWN_GET_DISCRETE_CHANNEL_COUNT(mixdown);
    if( codec & HB_ACODEC_PASS_FLAG )
    {
        // Bitrates don't apply to "lossless" audio (Passthru, FLAC)
        *low = *high = -1;
        return;
    }
    switch( codec )
    {
        case HB_ACODEC_FFFLAC:
            // Bitrates don't apply to "lossless" audio (Passthru, FLAC)
            *high = *low = -1;
            break;

        case HB_ACODEC_AC3:
            *low = 32 * channels;
            if (samplerate > 24000)
            {
                *high = 640;
            }
            else
            {
                *high = 320;
            }
            break;

        case HB_ACODEC_CA_AAC:
            if (samplerate > 32000)
            {
                *low = channels * 32;
                if (channels == 1)
                    *high = 256;
                if (channels == 2)
                    *high = 320;
                if (channels == 6)
                {
                    *low = 160;
                    *high = 768;
                }
            }
            else if (samplerate > 24000)
            {
                *low = channels * 24;
                *high = channels * 96;
                if (channels == 6)
                {
                    *low = 128;
                    *high = 448;
                }
            }
            else
            {
                *low = channels * 16;
                *high = channels * 64;
                if (channels == 6)
                {
                    *low = 80;
                    *high = 320;
                }
            }
            break;

        case HB_ACODEC_CA_HAAC:
            if (samplerate > 32000)
            {
                *low = channels * 16;
                *high = channels * 40;
                if (channels == 6)
                {
                    *low = 80;
                    *high = 192;
                }
            }
            else
            {
                *low = channels * 12;
                *high = channels * 40;
                if (channels == 6)
                {
                    *low = 64;
                    *high = 192;
                }
            }
            break;

        case HB_ACODEC_FAAC:
            *low = 32 * channels;
            if (samplerate > 24000)
            {
                *high = 160 * channels;
                if (*high > 768)
                    *high = 768;
            }
            else
            {
                *high = 96 * channels;
                if (*high > 480)
                    *high = 480;
            }
            break;

        case HB_ACODEC_FFAAC:
            *low = 32 * channels;
            if (samplerate > 24000)
            {
                *high = 160 * channels;
                if (*high > 768)
                    *high = 768;
            }
            else
            {
                *high = 96 * channels;
                if (*high > 480)
                    *high = 480;
            }
            break;

        case HB_ACODEC_VORBIS:
            *high = channels * 80;
            if (samplerate > 24000)
            {
                if (channels > 2)
                {
                    // Vorbis minimum is around 30kbps/ch for 6ch 
                    // at rates > 24k (32k/44.1k/48k) 
                    *low = 32 * channels;
                    *high = 128 * channels;
                }
                else
                {
                    // Allow 24kbps mono and 48kbps stereo at rates > 24k 
                    // (32k/44.1k/48k)
                    *low = 24 * channels;
                    if (samplerate > 32000)
                        *high = channels * 224;
                    else
                        *high = channels * 160;
                }
            }
            else
            {
                *low = channels * 16;
                *high = 80 * channels;
            }
            break;

        case HB_ACODEC_LAME:
            *low = hb_audio_bitrates[0].rate;
            if (samplerate > 24000)
                *high = 320;
            else
                *high = 160;
            break;
        
        default:
            *low = hb_audio_bitrates[0].rate;
            *high = hb_audio_bitrates[hb_audio_bitrates_count-1].rate;
            break;
    }
}

// Given an input bitrate, sanitize it.  Check low and high limits and
// make sure it is in the set of allowed bitrates.
int hb_get_best_audio_bitrate( uint32_t codec, int bitrate, int samplerate, int mixdown)
{
    int low, high;

    hb_get_audio_bitrate_limits(codec, samplerate, mixdown, &low, &high);
    if (bitrate > high)
        bitrate = high;
    if (bitrate < low)
        bitrate = low;
    bitrate = hb_find_closest_audio_bitrate(bitrate);
    return bitrate;
}

// Get the default bitrate for a given codec/samplerate/mixdown triplet.
int hb_get_default_audio_bitrate( uint32_t codec, int samplerate, int mixdown )
{
    int bitrate, channels;
    int sr_shift;

    if( codec & HB_ACODEC_PASS_FLAG )
        return -1;

    channels = HB_AMIXDOWN_GET_DISCRETE_CHANNEL_COUNT(mixdown);

    // Min bitrate is established such that we get good quality
    // audio as a minimum.
    sr_shift = (samplerate <= 24000) ? 1 : 0;

    switch ( codec )
    {
        case HB_ACODEC_FFFLAC:
            bitrate = -1;
            sr_shift = 0;
            break;
        case HB_ACODEC_AC3:
            if (channels == 1)
                bitrate = 96;
            else if (channels <= 2)
                bitrate = 224;
            else
                bitrate = 640;
            break;
        case HB_ACODEC_CA_HAAC:
            bitrate = channels * 32;
            break;
        default:
            bitrate = channels * 80;
            break;
    }
    bitrate >>= sr_shift;
    bitrate = hb_get_best_audio_bitrate( codec, bitrate, samplerate, mixdown );
    return bitrate;
}

// Get limits and hints for the UIs.
//
// granularity sets the minimum step increments that should be used
// (it's ok to round up to some nice multiple if you like)
//
// direction says whether 'low' limit is highest or lowest 
// quality (direction 0 == lowest value is worst quality)
void hb_get_audio_quality_limits(uint32_t codec, float *low, float *high, float *granularity, int *direction)
{
    switch( codec )
    {
        case HB_ACODEC_LAME:
            *direction = 1;
            *granularity = 0.5;
            *low = 0.;
            *high = 10.0;
            break;

        case HB_ACODEC_VORBIS:
            *direction = 0;
            *granularity = 0.5;
            *low = -2.0;
            *high = 10.0;
            break;

        case HB_ACODEC_CA_AAC:
            *direction = 0;
            *granularity = 9;
            *low = 0.;
            *high = 127.0;
            break;

        default:
            *direction = 0;
            *granularity = 1;
            *low = *high = -1.;
            break;
    }
}

float hb_get_best_audio_quality( uint32_t codec, float quality)
{
    float low, high, granularity;
    int direction;

    hb_get_audio_quality_limits(codec, &low, &high, &granularity, &direction);
    if (quality > high)
        quality = high;
    if (quality < low)
        quality = low;
    return quality;
}

float hb_get_default_audio_quality( uint32_t codec )
{
    float quality;
    switch( codec )
    {
        case HB_ACODEC_LAME:
            quality = 2.;
            break;

        case HB_ACODEC_VORBIS:
            quality = .5;
            break;

        case HB_ACODEC_CA_AAC:
            quality = 91.;
            break;

        default:
            quality = -1.;
            break;
    }
    return quality;
}

// Get limits and hints for the UIs.
//
// granularity sets the minimum step increments that should be used
// (it's ok to round up to some nice multiple if you like)
//
// direction says whether 'low' limit is highest or lowest 
// compression level (direction 0 == lowest value is worst compression level)
void hb_get_audio_compression_limits(uint32_t codec, float *low, float *high, float *granularity, int *direction)
{
    switch( codec )
    {
        case HB_ACODEC_FFFLAC:
            *direction = 0;
            *granularity = 1;
            *high = 12;
            *low = 0;
            break;

        case HB_ACODEC_LAME:
            *direction = 1;
            *granularity = 1;
            *high = 9;
            *low = 0;
            break;

        default:
            *direction = 0;
            *granularity = 1;
            *low = *high = -1;
            break;
    }
}

float hb_get_best_audio_compression( uint32_t codec, float compression)
{
    float low, high, granularity;
    int direction;

    hb_get_audio_compression_limits( codec, &low, &high, &granularity, &direction );
    if( compression > high )
        compression = high;
    if( compression < low )
        compression = low;
    return compression;
}

float hb_get_default_audio_compression( uint32_t codec )
{
    float compression;
    switch( codec )
    {
        case HB_ACODEC_FFFLAC:
            compression = 5;
            break;

        case HB_ACODEC_LAME:
            compression = 2;
            break;

        default:
            compression = -1;
            break;
    }
    return compression;
}

int hb_get_best_mixdown( uint32_t codec, int layout, int mixdown )
{

    int best_mixdown;
    
    if (codec & HB_ACODEC_PASS_FLAG)
    {
        // Audio pass-thru.  No mixdown.
        return HB_AMIXDOWN_NONE;
    }
    switch (layout & HB_INPUT_CH_LAYOUT_DISCRETE_NO_LFE_MASK)
    {
        // stereo input or something not handled below
        default:
        case HB_INPUT_CH_LAYOUT_STEREO:
            // mono gets mixed up to stereo & more than stereo gets mixed down
            best_mixdown = HB_AMIXDOWN_STEREO;
            break;

        // mono input
        case HB_INPUT_CH_LAYOUT_MONO:
            // everything else passes through
            best_mixdown = HB_AMIXDOWN_MONO;
            break;

        // dolby (DPL1 aka Dolby Surround = 4.0 matrix-encoded) input
        // the A52 flags don't allow for a way to distinguish between DPL1 and
        // DPL2 on a DVD so we always assume a DPL1 source for A52_DOLBY.
        case HB_INPUT_CH_LAYOUT_DOLBY:
            best_mixdown = HB_AMIXDOWN_DOLBY;
            break;

        // 4 channel discrete
        case HB_INPUT_CH_LAYOUT_2F2R:
        case HB_INPUT_CH_LAYOUT_3F1R:
            // a52dec and libdca can't upmix to 6ch, 
            // so we must downmix these.
            best_mixdown = HB_AMIXDOWN_DOLBYPLII;
            break;

        // 5, 6, 7, or 8 channel discrete
        case HB_INPUT_CH_LAYOUT_4F2R:
        case HB_INPUT_CH_LAYOUT_3F4R:
        case HB_INPUT_CH_LAYOUT_3F2R:
            if ( ! ( layout & HB_INPUT_CH_LAYOUT_HAS_LFE ) )
            {
                // we don't do 5 channel discrete so mixdown to DPLII
                // a52dec and libdca can't upmix to 6ch, 
                // so we must downmix this.
                best_mixdown = HB_AMIXDOWN_DOLBYPLII;
            }
            else
            {
                switch (codec)
                {
                    case HB_ACODEC_LAME:
                    case HB_ACODEC_FFAAC:
                        best_mixdown = HB_AMIXDOWN_DOLBYPLII;
                        break;

                    default:
                        best_mixdown = HB_AMIXDOWN_6CH;
                        break;
                }
            }
            break;
    }
    // return the best that is not greater than the requested mixdown
    // 0 means the caller requested the best available mixdown
    if( best_mixdown > mixdown && mixdown > 0 )
        best_mixdown = mixdown;
    
    return best_mixdown;
}

int hb_get_default_mixdown( uint32_t codec, int layout )
{
    int mixdown;
    switch (codec)
    {
        // the AC3 encoder defaults to the best mixdown up to 6-channel
        case HB_ACODEC_FFFLAC:
        case HB_ACODEC_AC3:
            mixdown = HB_AMIXDOWN_6CH;
            break;
        // other encoders default to the best mixdown up to DPLII
        default:
            mixdown = HB_AMIXDOWN_DOLBYPLII;
            break;
    }
    // return the best available mixdown up to the selected default
    return hb_get_best_mixdown( codec, layout, mixdown );
}

/**********************************************************************
 * hb_reduce
 **********************************************************************
 * Given a numerator (num) and a denominator (den), reduce them to an
 * equivalent fraction and store the result in x and y.
 *********************************************************************/
void hb_reduce( int *x, int *y, int num, int den )
{
    // find the greatest common divisor of num & den by Euclid's algorithm
    int n = num, d = den;
    while ( d )
    {
        int t = d;
        d = n % d;
        n = t;
    }

    // at this point n is the gcd. if it's non-zero remove it from num
    // and den. Otherwise just return the original values.
    if ( n )
    {
        *x = num / n;
        *y = den / n;
    }
    else
    {
        *x = num;
        *y = den;
    }
}

/**********************************************************************
 * hb_reduce64
 **********************************************************************
 * Given a numerator (num) and a denominator (den), reduce them to an
 * equivalent fraction and store the result in x and y.
 *********************************************************************/
void hb_reduce64( int64_t *x, int64_t *y, int64_t num, int64_t den )
{
    // find the greatest common divisor of num & den by Euclid's algorithm
    int64_t n = num, d = den;
    while ( d )
    {
        int64_t t = d;
        d = n % d;
        n = t;
    }

    // at this point n is the gcd. if it's non-zero remove it from num
    // and den. Otherwise just return the original values.
    if ( n )
    {
        num /= n;
        den /= n;
    }

    *x = num;
    *y = den;

}

void hb_limit_rational64( int64_t *x, int64_t *y, int64_t num, int64_t den, int64_t limit )
{
    hb_reduce64( &num, &den, num, den );
    if ( num < limit && den < limit )
    {
        *x = num;
        *y = den;
        return;
    }

    if ( num > den )
    {
        double div = (double)limit / num;
        num = limit;
        den *= div;
    }
    else
    {
        double div = (double)limit / den;
        den = limit;
        num *= div;
    }
    *x = num;
    *y = den;
}

/**********************************************************************
 * hb_fix_aspect
 **********************************************************************
 * Given the output width (if HB_KEEP_WIDTH) or height
 * (HB_KEEP_HEIGHT) and the current crop values, calculates the
 * correct height or width in order to respect the DVD aspect ratio
 *********************************************************************/
void hb_fix_aspect( hb_job_t * job, int keep )
{
    hb_title_t * title = job->title;
    int          i;
    int  min_width;
    int min_height;
    int    modulus;

    /* don't do anything unless the title has complete size info */
    if ( title->height == 0 || title->width == 0 || title->aspect == 0 )
    {
        hb_log( "hb_fix_aspect: incomplete info for title %d: "
                "height = %d, width = %d, aspect = %.3f",
                title->index, title->height, title->width, title->aspect );
        return;
    }

    // min_width and min_height should be multiples of modulus
    min_width    = 32;
    min_height   = 32;
    modulus      = job->modulus ? job->modulus : 16;

    for( i = 0; i < 4; i++ )
    {
        // Sanity check crop values are zero or positive multiples of 2
        if( i < 2 )
        {
            // Top, bottom
            job->crop[i] = MIN( EVEN( job->crop[i] ), EVEN( ( title->height / 2 ) - ( min_height / 2 ) ) );
            job->crop[i] = MAX( 0, job->crop[i] );
        }
        else
        {
            // Left, right
            job->crop[i] = MIN( EVEN( job->crop[i] ), EVEN( ( title->width / 2 ) - ( min_width / 2 ) ) );
            job->crop[i] = MAX( 0, job->crop[i] );
        }
    }

    double par = (double)title->width / ( (double)title->height * title->aspect );
    double cropped_sar = (double)( title->height - job->crop[0] - job->crop[1] ) /
                         (double)( title->width - job->crop[2] - job->crop[3] );
    double ar = par * cropped_sar;

    // Dimensions must be greater than minimum and multiple of modulus
    if( keep == HB_KEEP_WIDTH )
    {
        job->width  = MULTIPLE_MOD( job->width, modulus );
        job->width  = MAX( min_width, job->width );
        job->height = MULTIPLE_MOD( (uint64_t)( (double)job->width * ar ), modulus );
        job->height = MAX( min_height, job->height );
    }
    else
    {
        job->height = MULTIPLE_MOD( job->height, modulus );
        job->height = MAX( min_height, job->height );
        job->width  = MULTIPLE_MOD( (uint64_t)( (double)job->height / ar ), modulus );
        job->width  = MAX( min_width, job->width );
    }
}

/**********************************************************************
 * hb_list implementation
 **********************************************************************
 * Basic and slow, but enough for what we need
 *********************************************************************/

#define HB_LIST_DEFAULT_SIZE 20

struct hb_list_s
{
    /* Pointers to items in the list */
    void ** items;

    /* How many (void *) allocated in 'items' */
    int     items_alloc;

    /* How many valid pointers in 'items' */
    int     items_count;
};

/**********************************************************************
 * hb_list_init
 **********************************************************************
 * Allocates an empty list ready for HB_LIST_DEFAULT_SIZE items
 *********************************************************************/
hb_list_t * hb_list_init()
{
    hb_list_t * l;

    l              = calloc( sizeof( hb_list_t ), 1 );
    l->items       = calloc( HB_LIST_DEFAULT_SIZE * sizeof( void * ), 1 );
    l->items_alloc = HB_LIST_DEFAULT_SIZE;

    return l;
}

/**********************************************************************
 * hb_list_count
 **********************************************************************
 * Returns the number of items currently in the list
 *********************************************************************/
int hb_list_count( hb_list_t * l )
{
    return l->items_count;
}

/**********************************************************************
 * hb_list_add
 **********************************************************************
 * Adds an item at the end of the list, making it bigger if necessary.
 * Can safely be called with a NULL pointer to add, it will be ignored.
 *********************************************************************/
void hb_list_add( hb_list_t * l, void * p )
{
    if( !p )
    {
        return;
    }

    if( l->items_count == l->items_alloc )
    {
        /* We need a bigger boat */
        l->items_alloc += HB_LIST_DEFAULT_SIZE;
        l->items        = realloc( l->items,
                                   l->items_alloc * sizeof( void * ) );
    }

    l->items[l->items_count] = p;
    (l->items_count)++;
}

/**********************************************************************
 * hb_list_insert
 **********************************************************************
 * Adds an item at the specifiec position in the list, making it bigger
 * if necessary.
 * Can safely be called with a NULL pointer to add, it will be ignored.
 *********************************************************************/
void hb_list_insert( hb_list_t * l, int pos, void * p )
{
    if( !p )
    {
        return;
    }

    if( l->items_count == l->items_alloc )
    {
        /* We need a bigger boat */
        l->items_alloc += HB_LIST_DEFAULT_SIZE;
        l->items        = realloc( l->items,
                                   l->items_alloc * sizeof( void * ) );
    }

    if ( l->items_count != pos )
    {
        /* Shift all items after it sizeof( void * ) bytes earlier */
        memmove( &l->items[pos+1], &l->items[pos],
                 ( l->items_count - pos ) * sizeof( void * ) );
    }


    l->items[pos] = p;
    (l->items_count)++;
}

/**********************************************************************
 * hb_list_rem
 **********************************************************************
 * Remove an item from the list. Bad things will happen if called
 * with a NULL pointer or if the item is not in the list.
 *********************************************************************/
void hb_list_rem( hb_list_t * l, void * p )
{
    int i;

    /* Find the item in the list */
    for( i = 0; i < l->items_count; i++ )
    {
        if( l->items[i] == p )
        {
            break;
        }
    }

    /* Shift all items after it sizeof( void * ) bytes earlier */
    memmove( &l->items[i], &l->items[i+1],
             ( l->items_count - i - 1 ) * sizeof( void * ) );

    (l->items_count)--;
}

/**********************************************************************
 * hb_list_item
 **********************************************************************
 * Returns item at position i, or NULL if there are not that many
 * items in the list
 *********************************************************************/
void * hb_list_item( hb_list_t * l, int i )
{
    if( i < 0 || i >= l->items_count )
    {
        return NULL;
    }

    return l->items[i];
}

/**********************************************************************
 * hb_list_bytes
 **********************************************************************
 * Assuming all items are of type hb_buffer_t, returns the total
 * number of bytes in the list
 *********************************************************************/
int hb_list_bytes( hb_list_t * l )
{
    hb_buffer_t * buf;
    int           ret;
    int           i;

    ret = 0;
    for( i = 0; i < hb_list_count( l ); i++ )
    {
        buf  = hb_list_item( l, i );
        ret += buf->size - buf->cur;
    }

    return ret;
}

/**********************************************************************
 * hb_list_seebytes
 **********************************************************************
 * Assuming all items are of type hb_buffer_t, copy <size> bytes from
 * the list to <dst>, keeping the list unmodified.
 *********************************************************************/
void hb_list_seebytes( hb_list_t * l, uint8_t * dst, int size )
{
    hb_buffer_t * buf;
    int           copied;
    int           copying;
    int           i;

    for( i = 0, copied = 0; copied < size; i++ )
    {
        buf     = hb_list_item( l, i );
        copying = MIN( buf->size - buf->cur, size - copied );
        memcpy( &dst[copied], &buf->data[buf->cur], copying );
        copied += copying;
    }
}

/**********************************************************************
 * hb_list_getbytes
 **********************************************************************
 * Assuming all items are of type hb_buffer_t, copy <size> bytes from
 * the list to <dst>. What's copied is removed from the list.
 * The variable pointed by <pts> is set to the PTS of the buffer the
 * first byte has been got from.
 * The variable pointed by <pos> is set to the position of that byte
 * in that buffer.
 *********************************************************************/
void hb_list_getbytes( hb_list_t * l, uint8_t * dst, int size,
                       uint64_t * pts, uint64_t * pos )
{
    hb_buffer_t * buf;
    int           copied;
    int           copying;
    uint8_t       has_pts;

    /* So we won't have to deal with NULL pointers */
     uint64_t dummy1, dummy2;

    if( !pts ) pts = &dummy1;
    if( !pos ) pos = &dummy2;

    for( copied = 0, has_pts = 0; copied < size;  )
    {
        buf     = hb_list_item( l, 0 );
        copying = MIN( buf->size - buf->cur, size - copied );
        memcpy( &dst[copied], &buf->data[buf->cur], copying );

        if( !has_pts )
        {
            *pts    = buf->start;
            *pos    = buf->cur;
            has_pts = 1;
        }

        buf->cur += copying;
        if( buf->cur >= buf->size )
        {
            hb_list_rem( l, buf );
            hb_buffer_close( &buf );
        }

        copied += copying;
    }
}

/**********************************************************************
 * hb_list_empty
 **********************************************************************
 * Assuming all items are of type hb_buffer_t, close them all and
 * close the list.
 *********************************************************************/
void hb_list_empty( hb_list_t ** _l )
{
    hb_list_t * l = *_l;
    hb_buffer_t * b;

    while( ( b = hb_list_item( l, 0 ) ) )
    {
        hb_list_rem( l, b );
        hb_buffer_close( &b );
    }

    hb_list_close( _l );
}

/**********************************************************************
 * hb_list_close
 **********************************************************************
 * Free memory allocated by hb_list_init. Does NOT free contents of
 * items still in the list.
 *********************************************************************/
void hb_list_close( hb_list_t ** _l )
{
    hb_list_t * l = *_l;

    free( l->items );
    free( l );

    *_l = NULL;
}

int global_verbosity_level; //Necessary for hb_deep_log
/**********************************************************************
 * hb_valog
 **********************************************************************
 * If verbose mode is one, print message with timestamp. Messages
 * longer than 180 characters are stripped ;p
 *********************************************************************/
void hb_valog( hb_debug_level_t level, const char * prefix, const char * log, va_list args)
{
    char        string[362]; /* 360 chars + \n + \0 */
    time_t      _now;
    struct tm * now;

    if( !getenv( "HB_DEBUG" ) )
    {
        /* We don't want to print it */
        return;
    }

    if( global_verbosity_level < level )
    {
        /* Hiding message */
        return;
    }

    /* Get the time */
    _now = time( NULL );
    now  = localtime( &_now );
    if ( prefix && *prefix )
    {
        // limit the prefix length
        snprintf( string, 40, "[%02d:%02d:%02d] %s ",
                 now->tm_hour, now->tm_min, now->tm_sec, prefix );
    }
    else
    {
        sprintf( string, "[%02d:%02d:%02d] ",
                 now->tm_hour, now->tm_min, now->tm_sec );
    }
    int end = strlen( string );

    /* Convert the message to a string */
    vsnprintf( string + end, 361 - end, log, args );

    /* Add the end of line */
    strcat( string, "\n" );

    /* Print it */
    fprintf( stderr, "%s", string );
}

/**********************************************************************
 * hb_log
 **********************************************************************
 * If verbose mode is one, print message with timestamp. Messages
 * longer than 180 characters are stripped ;p
 *********************************************************************/
void hb_log( char * log, ... )
{
    va_list     args;

    va_start( args, log );
    hb_valog( 0, NULL, log, args );
    va_end( args );
}

/**********************************************************************
 * hb_deep_log
 **********************************************************************
 * If verbose mode is >= level, print message with timestamp. Messages
 * longer than 360 characters are stripped ;p
 *********************************************************************/
void hb_deep_log( hb_debug_level_t level, char * log, ... )
{
    va_list     args;

    va_start( args, log );
    hb_valog( level, NULL, log, args );
    va_end( args );
}

/**********************************************************************
 * hb_error
 **********************************************************************
 * Using whatever output is available display this error.
 *********************************************************************/
void hb_error( char * log, ... )
{
    char        string[181]; /* 180 chars + \0 */
    char        rep_string[181];
    static char last_string[181];
    static int  last_error_count = 0;
    static uint64_t last_series_error_time = 0;
    static hb_lock_t *mutex = 0;
    va_list     args;
    uint64_t time_now;

    /* Convert the message to a string */
    va_start( args, log );
    vsnprintf( string, 180, log, args );
    va_end( args );

    if( !mutex )
    {
        mutex = hb_lock_init();
    }

    hb_lock( mutex );

    time_now = hb_get_date();

    if( strcmp( string, last_string) == 0 )
    {
        /*
         * The last error and this one are the same, don't log it
         * just count it instead, unless it was more than one second
         * ago.
         */
        last_error_count++;
        if( last_series_error_time + ( 1000 * 1 ) > time_now )
        {
            hb_unlock( mutex );
            return;
        } 
    }
    
    /*
     * A new error, or the same one more than 10sec since the last one
     * did we have any of the same counted up?
     */
    if( last_error_count > 0 )
    {
        /*
         * Print out the last error to ensure context for the last 
         * repeated message.
         */
        if( error_handler )
        {
            error_handler( last_string );
        } else {
            hb_log( "%s", last_string );
        }
        
        if( last_error_count > 1 )
        {
            /*
             * Only print out the repeat message for more than 2 of the
             * same, since we just printed out two of them already.
             */
            snprintf( rep_string, 180, "Last error repeated %d times", 
                      last_error_count - 1 );
            
            if( error_handler )
            {
                error_handler( rep_string );
            } else {
                hb_log( "%s", rep_string );
            }
        }
        
        last_error_count = 0;
    }

    last_series_error_time = time_now;

    strcpy( last_string, string );

    /*
     * Got the error in a single string, send it off to be dispatched.
     */
    if( error_handler )
    {
        error_handler( string );
    } else {
        hb_log( "%s", string );
    }

    hb_unlock( mutex );
}

void hb_register_error_handler( hb_error_handler_t * handler )
{
    error_handler = handler;
}

/**********************************************************************
 * hb_title_init
 **********************************************************************
 *
 *********************************************************************/
hb_title_t * hb_title_init( char * path, int index )
{
    hb_title_t * t;

    t = calloc( sizeof( hb_title_t ), 1 );

    t->index         = index;
    t->playlist      = -1;
    t->list_audio    = hb_list_init();
    t->list_chapter  = hb_list_init();
    t->list_subtitle = hb_list_init();
    t->list_attachment = hb_list_init();
    strcat( t->path, path );
    // default to decoding mpeg2
    t->video_id      = 0xE0;
    t->video_codec   = WORK_DECMPEG2;
    t->angle_count   = 1;
    t->pixel_aspect_width = 1;
    t->pixel_aspect_height = 1;

    return t;
}

/**********************************************************************
 * hb_title_close
 **********************************************************************
 *
 *********************************************************************/
void hb_title_close( hb_title_t ** _t )
{
    hb_title_t * t = *_t;
    hb_audio_t * audio;
    hb_chapter_t * chapter;
    hb_subtitle_t * subtitle;
    hb_attachment_t * attachment;

    while( ( audio = hb_list_item( t->list_audio, 0 ) ) )
    {
        hb_list_rem( t->list_audio, audio );
        free( audio );
    }
    hb_list_close( &t->list_audio );

    while( ( chapter = hb_list_item( t->list_chapter, 0 ) ) )
    {
        hb_list_rem( t->list_chapter, chapter );
        free( chapter );
    }
    hb_list_close( &t->list_chapter );

    while( ( subtitle = hb_list_item( t->list_subtitle, 0 ) ) )
    {
        hb_list_rem( t->list_subtitle, subtitle );
        if ( subtitle->extradata )
        {
            free( subtitle->extradata );
            subtitle->extradata = NULL;
        }
        free( subtitle );
    }
    hb_list_close( &t->list_subtitle );
    
    while( ( attachment = hb_list_item( t->list_attachment, 0 ) ) )
    {
        hb_list_rem( t->list_attachment, attachment );
        if ( attachment->name )
        {
            free( attachment->name );
            attachment->name = NULL;
        }
        if ( attachment->data )
        {
            free( attachment->data );
            attachment->data = NULL;
        }
        free( attachment );
    }
    hb_list_close( &t->list_attachment );

    if( t->metadata )
    {
        if( t->metadata->coverart )
        {
            free( t->metadata->coverart );
        }
        free( t->metadata );
    }

    if ( t->video_codec_name )
    {
        free( t->video_codec_name );
    }

    free( t );
    *_t = NULL;
}

/**********************************************************************
 * hb_filter_close
 **********************************************************************
 *
 *********************************************************************/
void hb_filter_close( hb_filter_object_t ** _f )
{
    hb_filter_object_t * f = *_f;

    f->close( f->private_data );

    if( f->name )
        free( f->name );
    if( f->settings )
        free( f->settings );

    free( f );
    *_f = NULL;
}

/**********************************************************************
 * hb_audio_copy
 **********************************************************************
 *
 *********************************************************************/
hb_audio_t *hb_audio_copy(const hb_audio_t *src)
{
    hb_audio_t *audio = NULL;

    if( src )
    {
        audio = calloc(1, sizeof(*audio));
        memcpy(audio, src, sizeof(*audio));
    }
    return audio;
}

/**********************************************************************
 * hb_audio_new
 **********************************************************************
 *
 *********************************************************************/
void hb_audio_config_init(hb_audio_config_t * audiocfg)
{
    /* Set read only paramaters to invalid values */
    audiocfg->in.codec = 0xDEADBEEF;
    audiocfg->in.bitrate = -1;
    audiocfg->in.samplerate = -1;
    audiocfg->in.channel_layout = 0;
    audiocfg->in.channel_map = NULL;
    audiocfg->in.version = 0;
    audiocfg->in.mode = 0;
    audiocfg->flags.ac3 = 0;
    audiocfg->lang.description[0] = 0;
    audiocfg->lang.simple[0] = 0;
    audiocfg->lang.iso639_2[0] = 0;

    /* Initalize some sensable defaults */
    audiocfg->in.track = audiocfg->out.track = 0;
    audiocfg->out.codec = HB_ACODEC_FAAC;
    audiocfg->out.bitrate = -1;
    audiocfg->out.quality = -1;
    audiocfg->out.compression_level = -1;
    audiocfg->out.samplerate = -1;
    audiocfg->out.mixdown = -1;
    audiocfg->out.dynamic_range_compression = 0;
    audiocfg->out.name = NULL;

}

/**********************************************************************
 * hb_audio_add
 **********************************************************************
 *
 *********************************************************************/
int hb_audio_add(const hb_job_t * job, const hb_audio_config_t * audiocfg)
{
    hb_title_t *title = job->title;
    hb_audio_t *audio;

    audio = hb_audio_copy( hb_list_item( title->list_audio, audiocfg->in.track ) );
    if( audio == NULL )
    {
        /* We fail! */
        return 0;
    }

    if( (audiocfg->in.bitrate != -1) && (audiocfg->in.codec != 0xDEADBEEF) )
    {
        /* This most likely means the client didn't call hb_audio_config_init
         * so bail. */
        return 0;
    }

    /* Set the job's "in track" to the value passed in audiocfg.
     * HandBrakeCLI assumes this value is preserved in the jobs
     * audio list, but in.track in the title's audio list is not 
     * required to be the same. */
    audio->config.in.track = audiocfg->in.track;

    /* Really shouldn't ignore the passed out track, but there is currently no
     * way to handle duplicates or out-of-order track numbers. */
    audio->config.out.track = hb_list_count(job->list_audio) + 1;
    audio->config.out.codec = audiocfg->out.codec;
    if((audiocfg->out.codec & HB_ACODEC_PASS_FLAG) &&
       ((audiocfg->out.codec == HB_ACODEC_AUTO_PASS) ||
        (audiocfg->out.codec & audio->config.in.codec & HB_ACODEC_PASS_MASK)))
    {
        /* Pass-through, copy from input. */
        audio->config.out.samplerate = audio->config.in.samplerate;
        audio->config.out.bitrate = audio->config.in.bitrate;
        audio->config.out.mixdown = 0;
        audio->config.out.dynamic_range_compression = 0;
        audio->config.out.gain = 0;
        audio->config.out.compression_level = -1;
        audio->config.out.quality = -1;
    }
    else
    {
        /* Non pass-through, use what is given. */
        audio->config.out.codec &= ~HB_ACODEC_PASS_FLAG;
        audio->config.out.samplerate = audiocfg->out.samplerate;
        audio->config.out.bitrate = audiocfg->out.bitrate;
        audio->config.out.compression_level = audiocfg->out.compression_level;
        audio->config.out.quality = audiocfg->out.quality;
        audio->config.out.dynamic_range_compression = audiocfg->out.dynamic_range_compression;
        audio->config.out.mixdown = audiocfg->out.mixdown;
        audio->config.out.gain = audiocfg->out.gain;
    }
    if (audiocfg->out.name && *audiocfg->out.name)
    {
        audio->config.out.name = audiocfg->out.name;
    }

    hb_list_add(job->list_audio, audio);
    return 1;
}

hb_audio_config_t * hb_list_audio_config_item(hb_list_t * list, int i)
{
    hb_audio_t *audio = NULL;

    if( (audio = hb_list_item(list, i)) )
        return &(audio->config);

    return NULL;
}

/**********************************************************************
 * hb_subtitle_copy
 **********************************************************************
 *
 *********************************************************************/
hb_subtitle_t *hb_subtitle_copy(const hb_subtitle_t *src)
{
    hb_subtitle_t *subtitle = NULL;

    if( src )
    {
        subtitle = calloc(1, sizeof(*subtitle));
        memcpy(subtitle, src, sizeof(*subtitle));
        if ( src->extradata )
        {
            subtitle->extradata = malloc( src->extradata_size );
            memcpy( subtitle->extradata, src->extradata, src->extradata_size );
        }
    }
    return subtitle;
}

/**********************************************************************
 * hb_subtitle_add
 **********************************************************************
 *
 *********************************************************************/
int hb_subtitle_add(const hb_job_t * job, const hb_subtitle_config_t * subtitlecfg, int track)
{
    hb_title_t *title = job->title;
    hb_subtitle_t *subtitle;

    subtitle = hb_subtitle_copy( hb_list_item( title->list_subtitle, track ) );
    if( subtitle == NULL )
    {
        /* We fail! */
        return 0;
    }
    subtitle->config = *subtitlecfg;
    hb_list_add(job->list_subtitle, subtitle);
    return 1;
}

int hb_srt_add( const hb_job_t * job, 
                const hb_subtitle_config_t * subtitlecfg, 
                const char *lang )
{
    hb_subtitle_t *subtitle;
    iso639_lang_t *language = NULL;
    int retval = 0;

    subtitle = calloc( 1, sizeof( *subtitle ) );
    
    subtitle->id = (hb_list_count(job->list_subtitle) << 8) | 0xFF;
    subtitle->format = TEXTSUB;
    subtitle->source = SRTSUB;

    language = lang_for_code2( lang );

    if( language )
    {

        strcpy( subtitle->lang, language->eng_name );
        strncpy( subtitle->iso639_2, lang, 4 );
        
        subtitle->config = *subtitlecfg;
        subtitle->config.dest = PASSTHRUSUB;

        hb_list_add(job->list_subtitle, subtitle);
        retval = 1;
    }
    return retval;
}

char * hb_strdup_printf( const char * fmt, ... )
{
    int       len;
    va_list   ap;
    int       size = 256;
    char    * str;
    char    * tmp;

    str = malloc( size );
    if ( str == NULL )
        return NULL;

    while (1) 
    {
        /* Try to print in the allocated space. */
        va_start( ap, fmt );
        len = vsnprintf( str, size, fmt, ap );
        va_end( ap );

        /* If that worked, return the string. */
        if ( len > -1 && len < size )
        {
            return str;
        }

        /* Else try again with more space. */
        if ( len > -1 )     /* glibc 2.1 */
            size = len + 1; /* precisely what is needed */
        else                /* glibc 2.0 */
            size *= 2;      /* twice the old size */
        tmp = realloc( str, size );
        if ( tmp == NULL )
        {
            free( str );
            return NULL;
        }
        else
            str = tmp;
    }
}

/**********************************************************************
 * hb_attachment_copy
 **********************************************************************
 *
 *********************************************************************/
hb_attachment_t *hb_attachment_copy(const hb_attachment_t *src)
{
    hb_attachment_t *attachment = NULL;

    if( src )
    {
        attachment = calloc(1, sizeof(*attachment));
        memcpy(attachment, src, sizeof(*attachment));
        if ( src->name )
        {
            attachment->name = strdup( src->name );
        }
        if ( src->data )
        {
            attachment->data = malloc( src->size );
            memcpy( attachment->data, src->data, src->size );
        }
    }
    return attachment;
}

/**********************************************************************
 * hb_yuv2rgb
 **********************************************************************
 * Converts a YCrCb pixel to an RGB pixel.
 * 
 * This conversion is lossy (due to rounding and clamping).
 * 
 * Algorithm:
 *   http://en.wikipedia.org/w/index.php?title=YCbCr&oldid=361987695#Technical_details
 *********************************************************************/
int hb_yuv2rgb(int yuv)
{
    double y, Cr, Cb;
    int r, g, b;

    y  = (yuv >> 16) & 0xff;
    Cr = (yuv >>  8) & 0xff;
    Cb = (yuv      ) & 0xff;

    r = 1.164 * (y - 16)                      + 1.596 * (Cr - 128);
    g = 1.164 * (y - 16) - 0.392 * (Cb - 128) - 0.813 * (Cr - 128);
    b = 1.164 * (y - 16) + 2.017 * (Cb - 128);
    
    r = (r < 0) ? 0 : r;
    g = (g < 0) ? 0 : g;
    b = (b < 0) ? 0 : b;
    
    r = (r > 255) ? 255 : r;
    g = (g > 255) ? 255 : g;
    b = (b > 255) ? 255 : b;
    
    return (r << 16) | (g << 8) | b;
}

/**********************************************************************
 * hb_rgb2yuv
 **********************************************************************
 * Converts an RGB pixel to a YCrCb pixel.
 * 
 * This conversion is lossy (due to rounding and clamping).
 * 
 * Algorithm:
 *   http://en.wikipedia.org/w/index.php?title=YCbCr&oldid=361987695#Technical_details
 *********************************************************************/
int hb_rgb2yuv(int rgb)
{
    double r, g, b;
    int y, Cr, Cb;
    
    r = (rgb >> 16) & 0xff;
    g = (rgb >>  8) & 0xff;
    b = (rgb      ) & 0xff;

    y  =  16. + ( 0.257 * r) + (0.504 * g) + (0.098 * b);
    Cb = 128. + (-0.148 * r) - (0.291 * g) + (0.439 * b);
    Cr = 128. + ( 0.439 * r) - (0.368 * g) - (0.071 * b);
    
    y = (y < 0) ? 0 : y;
    Cb = (Cb < 0) ? 0 : Cb;
    Cr = (Cr < 0) ? 0 : Cr;
    
    y = (y > 255) ? 255 : y;
    Cb = (Cb > 255) ? 255 : Cb;
    Cr = (Cr > 255) ? 255 : Cr;
    
    return (y << 16) | (Cr << 8) | Cb;
}

const char * hb_subsource_name( int source )
{
    switch (source)
    {
        case VOBSUB:
            return "VOBSUB";
        case SRTSUB:
            return "SRT";
        case CC608SUB:
            return "CC";
        case CC708SUB:
            return "CC";
        case UTF8SUB:
            return "UTF-8";
        case TX3GSUB:
            return "TX3G";
        case SSASUB:
            return "SSA";
        default:
            return "Unknown";
    }
}

void hb_hexdump( hb_debug_level_t level, const char * label, const uint8_t * data, int len )
{
    int ii;
    char line[80], ascii[19], *p;

    ascii[18] = 0;
    ascii[0] = '|';
    ascii[17] = '|';
    memset(&ascii[1], '.', 16);
    p = line;
    if( label )
        hb_deep_log(level, "++++ %s ++++", label);
    else
        hb_deep_log(level, "++++++++++++");
    for( ii = 0; ii < len; ii++ )
    {
        if( ( ii & 0x0f ) == 0x0f )
        {
            p += sprintf( p, "%02x", data[ii] );
            hb_deep_log( level, "    %-50s%20s", line, ascii );
            memset(&ascii[1], '.', 16);
            p = line;
        }
        else if( ( ii & 0x07 ) == 0x07 )
        {
            p += sprintf( p, "%02x  ", data[ii] );
        }
        else
        {
            p += sprintf( p, "%02x ", data[ii] );
        }
        if( isgraph( data[ii] ) )
            ascii[(ii & 0x0f) + 1] = data[ii];
        else
            ascii[(ii & 0x0f) + 1] = '.';
    }
    ascii[ii] = 0;
    if( p != line )
    {
        hb_deep_log( level, "    %-50s%20s", line, ascii );
    }
}