path: root/libhb/encx264.c

/* $Id: encx264.c,v 1.21 2005/11/04 13:09:41 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 "hb.h"

#include "x264.h"

int  encx264Init( hb_work_object_t *, hb_job_t * );
int  encx264Work( hb_work_object_t *, hb_buffer_t **, hb_buffer_t ** );
void encx264Close( hb_work_object_t * );

hb_work_object_t hb_encx264 =
{
    WORK_ENCX264,
    "H.264/AVC encoder (libx264)",
    encx264Init,
    encx264Work,
    encx264Close
};

#define DTS_BUFFER_SIZE 32

/*
 * The frame info struct remembers information about each frame across calls
 * to x264_encoder_encode. Since frames are uniquely identified by their
 * timestamp, we use some bits of the timestamp as an index. The LSB is
 * chosen so that two successive frames will have different values in the
 * bits over any plausible range of frame rates. (Starting with bit 8 allows
 * any frame rate slower than 352fps.) The MSB determines the size of the array.
 * It is chosen so that two frames can't use the same slot during the
 * encoder's max frame delay (set by the standard as 16 frames) and so
 * that, up to some minimum frame rate, frames are guaranteed to map to
 * different slots. (An MSB of 17 which is 2^(17-8+1) = 1024 slots guarantees
 * no collisions down to a rate of .7 fps).
 */
#define FRAME_INFO_MAX2 (8)     // 2^8 = 256; 90000/256 = 352 frames/sec
#define FRAME_INFO_MIN2 (17)    // 2^17 = 128K; 90000/131072 = 1.4 frames/sec
#define FRAME_INFO_SIZE (1 << (FRAME_INFO_MIN2 - FRAME_INFO_MAX2 + 1))
#define FRAME_INFO_MASK (FRAME_INFO_SIZE - 1)

struct hb_work_private_s
{
    hb_job_t       * job;
    x264_t         * x264;
    x264_picture_t   pic_in;
    uint8_t        * grey_data;

    uint32_t       frames_in;
    uint32_t       frames_out;
    uint32_t       frames_split; // number of frames we had to split
    int            chap_mark;   // saved chap mark when we're propagating it
    int64_t        last_stop;   // Debugging - stop time of previous input frame
    int64_t        next_chap;

    struct {
        int64_t duration;
    } frame_info[FRAME_INFO_SIZE];

    char             filename[1024];
};

/***********************************************************************
 * hb_work_encx264_init
 ***********************************************************************
 *
 **********************************************************************/
int encx264Init( hb_work_object_t * w, hb_job_t * job )
{
    x264_param_t       param;
    x264_nal_t       * nal;
    int                nal_count;

    hb_work_private_t * pv = calloc( 1, sizeof( hb_work_private_t ) );
    w->private_data = pv;

    pv->job = job;

    memset( pv->filename, 0, 1024 );
    hb_get_tempory_filename( job->h, pv->filename, "x264.log" );

    x264_param_default( &param );
    
    /* Enable metrics */
    param.analyse.b_psnr = 1;
    param.analyse.b_ssim = 1;

    /* QuickTime has trouble with very low QPs (resulting in visual artifacts).
     * Known to affect QuickTime 7, QuickTime X and iTunes.
     * Testing shows that a qpmin of 3 works.
     */
    param.rc.i_qp_min = 3;
    
    param.i_threads    = ( hb_get_cpu_count() * 3 / 2 );
    param.i_width      = job->width;
    param.i_height     = job->height;
    if( job->pass == 2 && job->cfr != 1 )
    {
        hb_interjob_t * interjob = hb_interjob_get( job->h );
        param.i_fps_num = interjob->vrate;
        param.i_fps_den = interjob->vrate_base;
    }
    else
    {
        param.i_fps_num = job->vrate;
        param.i_fps_den = job->vrate_base;
    }
    if ( job->cfr == 1 )
    {
        param.i_timebase_num   = 0;
        param.i_timebase_den   = 0;
        param.b_vfr_input = 0;
    }
    else
    {
        param.i_timebase_num   = 1;
        param.i_timebase_den   = 90000;
    }

    /* Disable annexb. Inserts size into nal header instead of start code */
    param.b_annexb     = 0;

    /* Set min:max keyframe intervals to 1:10 of fps.
       adjust +0.5 for when fps has remainder to bump
       { 23.976, 29.976, 59.94 } to { 24, 30, 60 } */
    param.i_keyint_min = (int)( (double)job->vrate / (double)job->vrate_base + 0.5 );
    param.i_keyint_max = 10 * param.i_keyint_min;

    param.i_log_level  = X264_LOG_INFO;
    
    /*
        This section passes the string advanced_opts to libx264 for parsing into
        parameter names and values.

        The string is set up like this:
        option1=value1:option2=value 2

        So, you have to iterate through based on the colons, and then put
        the left side of the equals sign in "name" and the right side into
        "value." Then you hand those strings off to x264 for interpretation.

        This is all based on the universal x264 option handling Loren
        Merritt implemented in the Mplayer/Mencoder project.
     */

    if( job->advanced_opts != NULL && *job->advanced_opts != '\0' )
    {
        char *x264opts, *x264opts_start;

        x264opts = x264opts_start = strdup(job->advanced_opts);

        while( x264opts_start && *x264opts )
        {
            char *name = x264opts;
            char *value;
            int ret;

            x264opts += strcspn( x264opts, ":" );
            if( *x264opts )
            {
                *x264opts = 0;
                x264opts++;
            }

            value = strchr( name, '=' );
            if( value )
            {
                *value = 0;
                value++;
            }

            /* Here's where the strings are passed to libx264 for parsing. */
            ret = x264_param_parse( &param, name, value );

            /* Let x264 sanity check the options for us*/
            if( ret == X264_PARAM_BAD_NAME )
                hb_log( "x264 options: Unknown suboption %s", name );
            if( ret == X264_PARAM_BAD_VALUE )
                hb_log( "x264 options: Bad argument %s=%s", name, value ? value : "(null)" );
        }
        free(x264opts_start);
    }
    
    /* B-frames are on by default.*/
    job->areBframes = 1;
    
    if( param.i_bframe && param.i_bframe_pyramid )
    {
        /* Note b-pyramid here, so the initial delay can be doubled */
        job->areBframes = 2;
    }
    else if( !param.i_bframe )
    {
        /*
         When B-frames are enabled, the max frame count increments
         by 1 (regardless of the number of B-frames). If you don't
         change the duration of the video track when you mux, libmp4
         barfs.  So, check if the x264opts aren't using B-frames, and
         when they aren't, set the boolean job->areBframes as false.
         */
        job->areBframes = 0;
    }
    
    /* For 25 fps sources, HandBrake's explicit keyints will match the x264 defaults:
       min-keyint 25 (same as auto), keyint 250 */
    if( param.i_keyint_min != 25 || param.i_keyint_max != 250 )
    {
        int min_auto;

        if ( param.i_fps_num / param.i_fps_den < param.i_keyint_max / 10 )
            min_auto = param.i_fps_num / param.i_fps_den;
        else
            min_auto = param.i_keyint_max / 10;

        char min[40], max[40];
        param.i_keyint_min == X264_KEYINT_MIN_AUTO ? 
            snprintf( min, 40, "auto (%d)", min_auto ) : 
            snprintf( min, 40, "%d", param.i_keyint_min );

        param.i_keyint_max == X264_KEYINT_MAX_INFINITE ? 
            snprintf( max, 40, "infinite" ) : 
            snprintf( max, 40, "%d", param.i_keyint_max );

        hb_log( "encx264: min-keyint: %s, keyint: %s", min, max );
    }

    /* set up the VUI color model & gamma to match what the COLR atom
     * set in muxmp4.c says. See libhb/muxmp4.c for notes. */
    if( job->color_matrix == 1 )
    {
        // ITU BT.601 DVD or SD TV content
        param.vui.i_colorprim = 6;
        param.vui.i_transfer = 1;
        param.vui.i_colmatrix = 6;
    }
    else if( job->color_matrix == 2 )
    {
        // ITU BT.709 HD content
        param.vui.i_colorprim = 1;
        param.vui.i_transfer = 1;
        param.vui.i_colmatrix = 1;
    }
    else if ( job->title->width >= 1280 || job->title->height >= 720 )
    {
        // we guess that 720p or above is ITU BT.709 HD content
        param.vui.i_colorprim = 1;
        param.vui.i_transfer = 1;
        param.vui.i_colmatrix = 1;
    }
    else
    {
        // ITU BT.601 DVD or SD TV content
        param.vui.i_colorprim = 6;
        param.vui.i_transfer = 1;
        param.vui.i_colmatrix = 6;
    }

    if( job->anamorphic.mode )
    {
        param.vui.i_sar_width  = job->anamorphic.par_width;
        param.vui.i_sar_height = job->anamorphic.par_height;

        hb_log( "encx264: encoding with stored aspect %d/%d",
                param.vui.i_sar_width, param.vui.i_sar_height );
    }


    if( job->vquality >= 0 )
    {
        /* Constant RF */
        param.rc.i_rc_method = X264_RC_CRF;
        param.rc.f_rf_constant = job->vquality;
        hb_log( "encx264: Encoding at constant RF %f", param.rc.f_rf_constant );
    }
    else
    {
        /* Average bitrate */
        param.rc.i_rc_method = X264_RC_ABR;
        param.rc.i_bitrate = job->vbitrate;
        switch( job->pass )
        {
            case 1:
                param.rc.b_stat_write  = 1;
                param.rc.psz_stat_out = pv->filename;
                break;
            case 2:
                param.rc.b_stat_read = 1;
                param.rc.psz_stat_in = pv->filename;
                break;
        }
    }

    hb_deep_log( 2, "encx264: opening libx264 (pass %d)", job->pass );
    pv->x264 = x264_encoder_open( &param );

    x264_encoder_headers( pv->x264, &nal, &nal_count );

    /* Sequence Parameter Set */
    memcpy(w->config->h264.sps, nal[0].p_payload + 4, nal[0].i_payload - 4);
    w->config->h264.sps_length = nal[0].i_payload - 4;

    /* Picture Parameter Set */
    memcpy(w->config->h264.pps, nal[1].p_payload + 4, nal[1].i_payload - 4);
    w->config->h264.pps_length = nal[1].i_payload - 4;

    x264_picture_init( &pv->pic_in );

    pv->pic_in.img.i_csp = X264_CSP_I420;
    pv->pic_in.img.i_plane = 3;
    pv->pic_in.img.i_stride[0] = job->width;
    pv->pic_in.img.i_stride[2] = pv->pic_in.img.i_stride[1] = ( ( job->width + 1 ) >> 1 );

    if( job->grayscale )
    {
        int uvsize = ( (job->width + 1) >> 1 ) * ( (job->height + 1) >> 1 );
        pv->grey_data = malloc( uvsize );
        memset( pv->grey_data, 0x80, uvsize );
        pv->pic_in.img.plane[1] = pv->pic_in.img.plane[2] = pv->grey_data;
    }

    return 0;
}

void encx264Close( hb_work_object_t * w )
{
    hb_work_private_t * pv = w->private_data;

    if ( pv->frames_split )
    {
        hb_log( "encx264: %u frames had to be split (%u in, %u out)",
                pv->frames_split, pv->frames_in, pv->frames_out );
    }
    free( pv->grey_data );
    x264_encoder_close( pv->x264 );
    free( pv );
    w->private_data = NULL;

    /* TODO */
}

/*
 * see comments in definition of 'frame_info' in pv struct for description
 * of what these routines are doing.
 */
static void save_frame_info( hb_work_private_t * pv, hb_buffer_t * in )
{
    int i = (in->start >> FRAME_INFO_MAX2) & FRAME_INFO_MASK;
    pv->frame_info[i].duration = in->stop - in->start;
}

static int64_t get_frame_duration( hb_work_private_t * pv, int64_t pts )
{
    int i = (pts >> FRAME_INFO_MAX2) & FRAME_INFO_MASK;
    return pv->frame_info[i].duration;
}

static hb_buffer_t *nal_encode( hb_work_object_t *w, x264_picture_t *pic_out,
                                int i_nal, x264_nal_t *nal )
{
    hb_buffer_t *buf = NULL;
    hb_work_private_t *pv = w->private_data;
    hb_job_t *job = pv->job;

    /* Should be way too large */
    buf = hb_video_buffer_init( job->width, job->height );
    buf->size = 0;
    buf->frametype = 0;

    // use the pts to get the original frame's duration.
    int64_t duration  = get_frame_duration( pv, pic_out->i_pts );
    buf->start = pic_out->i_pts;
    buf->stop  = pic_out->i_pts + duration;
    buf->renderOffset = pic_out->i_dts;
    if ( !w->config->h264.init_delay && pic_out->i_dts < 0 )
    {
        w->config->h264.init_delay = -pic_out->i_dts;
    }

    /* Encode all the NALs we were given into buf.
       NOTE: This code assumes one video frame per NAL (but there can
             be other stuff like SPS and/or PPS). If there are multiple
             frames we only get the duration of the first which will
             eventually screw up the muxer & decoder. */
    int i;
    for( i = 0; i < i_nal; i++ )
    {
        int size = nal[i].i_payload;
        memcpy(buf->data + buf->size, nal[i].p_payload, size);
        if( size < 1 )
        {
            continue;
        }

        /* H.264 in .mp4 or .mkv */
        switch( nal[i].i_type )
        {
            /* Sequence Parameter Set & Program Parameter Set go in the
             * mp4 header so skip them here
             */
            case NAL_SPS:
            case NAL_PPS:
                continue;

            case NAL_SLICE:
            case NAL_SLICE_IDR:
            case NAL_SEI:
            default:
                break;
        }

        /* Decide what type of frame we have. */
        switch( pic_out->i_type )
        {
            case X264_TYPE_IDR:
                buf->frametype = HB_FRAME_IDR;
                /* if we have a chapter marker pending and this
                   frame's presentation time stamp is at or after
                   the marker's time stamp, use this as the
                   chapter start. */
                if( pv->next_chap != 0 && pv->next_chap <= pic_out->i_pts )
                {
                    pv->next_chap = 0;
                    buf->new_chap = pv->chap_mark;
                }
                break;

            case X264_TYPE_I:
                buf->frametype = HB_FRAME_I;
                break;

            case X264_TYPE_P:
                buf->frametype = HB_FRAME_P;
                break;

            case X264_TYPE_B:
                buf->frametype = HB_FRAME_B;
                break;

        /*  This is for b-pyramid, which has reference b-frames
            However, it doesn't seem to ever be used... */
            case X264_TYPE_BREF:
                buf->frametype = HB_FRAME_BREF;
                break;

            // If it isn't the above, what type of frame is it??
            default:
                buf->frametype = 0;
                break;
        }

        /* Since libx264 doesn't tell us when b-frames are
           themselves reference frames, figure it out on our own. */
        if( (buf->frametype == HB_FRAME_B) &&
            (nal[i].i_ref_idc != NAL_PRIORITY_DISPOSABLE) )
            buf->frametype = HB_FRAME_BREF;

        /* Expose disposable bit to muxer. */
        if( nal[i].i_ref_idc == NAL_PRIORITY_DISPOSABLE )
            buf->flags &= ~HB_FRAME_REF;
        else
            buf->flags |= HB_FRAME_REF;

        buf->size += size;
    }
    // make sure we found at least one video frame
    if ( buf->size <= 0 )
    {
        // no video - discard the buf
        hb_buffer_close( &buf );
    }
    return buf;
}

static hb_buffer_t *x264_encode( hb_work_object_t *w, hb_buffer_t *in )
{
    hb_work_private_t *pv = w->private_data;
    hb_job_t *job = pv->job;

    /* Point x264 at our current buffers Y(UV) data.  */
    pv->pic_in.img.plane[0] = in->data;

    int uvsize = ( (job->width + 1) >> 1 ) * ( (job->height + 1) >> 1 );
    if( !job->grayscale )
    {
        /* Point x264 at our buffers (Y)UV data */
        pv->pic_in.img.plane[1] = in->data + job->width * job->height;
        pv->pic_in.img.plane[2] = pv->pic_in.img.plane[1] + uvsize;
    }
    if( in->new_chap && job->chapter_markers )
    {
        /* chapters have to start with an IDR frame so request that this
           frame be coded as IDR. Since there may be up to 16 frames
           currently buffered in the encoder remember the timestamp so
           when this frame finally pops out of the encoder we'll mark
           its buffer as the start of a chapter. */
        pv->pic_in.i_type = X264_TYPE_IDR;
        if( pv->next_chap == 0 )
        {
            pv->next_chap = in->start;
            pv->chap_mark = in->new_chap;
        }
        /* don't let 'work_loop' put a chapter mark on the wrong buffer */
        in->new_chap = 0;
    }
    else
    {
        pv->pic_in.i_type = X264_TYPE_AUTO;
    }

    /* XXX this is temporary debugging code to check that the upstream
     * modules (render & sync) have generated a continuous, self-consistent
     * frame stream with the current frame's start time equal to the
     * previous frame's stop time.
     */
    if( pv->last_stop != in->start )
    {
        hb_log("encx264 input continuity err: last stop %"PRId64"  start %"PRId64,
                pv->last_stop, in->start);
    }
    pv->last_stop = in->stop;

    // Remember info about this frame that we need to pass across
    // the x264_encoder_encode call (since it reorders frames).
    save_frame_info( pv, in );

    /* Feed the input PTS to x264 so it can figure out proper output PTS */
    pv->pic_in.i_pts = in->start;

    x264_picture_t pic_out;
    int i_nal;
    x264_nal_t *nal;

    x264_encoder_encode( pv->x264, &nal, &i_nal, &pv->pic_in, &pic_out );
    if ( i_nal > 0 )
    {
        return nal_encode( w, &pic_out, i_nal, nal );
    }
    return NULL;
}

int encx264Work( hb_work_object_t * w, hb_buffer_t ** buf_in,
                  hb_buffer_t ** buf_out )
{
    hb_work_private_t *pv = w->private_data;
    hb_buffer_t *in = *buf_in;

    *buf_out = NULL;

    if( in->size <= 0 )
    {
        // EOF on input. Flush any frames still in the decoder then
        // send the eof downstream to tell the muxer we're done.
        x264_picture_t pic_out;
        int i_nal;
        x264_nal_t *nal;
        hb_buffer_t *last_buf = NULL;

        while ( x264_encoder_delayed_frames( pv->x264 ) )
        {
            x264_encoder_encode( pv->x264, &nal, &i_nal, NULL, &pic_out );
            if ( i_nal == 0 )
                continue;
            if ( i_nal < 0 )
                break;

            hb_buffer_t *buf = nal_encode( w, &pic_out, i_nal, nal );
            if ( buf )
            {
                ++pv->frames_out;
                if ( last_buf == NULL )
                    *buf_out = buf;
                else
                    last_buf->next = buf;
                last_buf = buf;
            }
        }
        // Flushed everything - add the eof to the end of the chain.
        if ( last_buf == NULL )
            *buf_out = in;
        else
            last_buf->next = in;

        *buf_in = NULL;
        return HB_WORK_DONE;
    }

    // Not EOF - encode the packet & wrap it in a NAL
    ++pv->frames_in;
    ++pv->frames_out;
    *buf_out = x264_encode( w, in );
    return HB_WORK_OK;
}