path: root/libhb/muxmp4.c

/* $Id: muxmp4.c,v 1.24 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. */

/* libmp4v2 header */
#include "mp4.h"

#include "hb.h"

void AddIPodUUID(MP4FileHandle, MP4TrackId);

struct hb_mux_object_s
{
    HB_MUX_COMMON;

    hb_job_t * job;

    /* libmp4v2 handle */
    MP4FileHandle file;

    /* Cumulated durations so far, in output & input timescale units (see MP4Mux) */
    int64_t sum_dur;        // duration in output timescale units
    int64_t sum_dur_in;     // duration in input 90KHz timescale units

    // bias to keep render offsets in ctts atom positive (set up by encx264)
    int64_t init_delay;

    /* Chapter state information for muxing */
    MP4TrackId chapter_track;
    int current_chapter;
    uint64_t chapter_duration;

    /* Sample rate of the first audio track.
     * Used for the timescale
     */
    int samplerate;
};

struct hb_mux_data_s
{
    MP4TrackId track;
};

struct hb_text_sample_s
{
    uint8_t     sample[1280];
    uint32_t    length;
    MP4Duration duration;
};

/**********************************************************************
 * MP4CreateTextSample
 **********************************************************************
 * Creates a buffer for a text track sample
 *********************************************************************/
static struct hb_text_sample_s *MP4CreateTextSample( char *textString, uint64_t duration )
{
    struct hb_text_sample_s *sample = NULL;
    int stringLength = strlen(textString);
    int x;

    if( stringLength < 1024 )
    {
        sample = malloc( sizeof( struct hb_text_sample_s ) );

        //textLength = (stringLength; // Account for BOM
        sample->length = stringLength + 2 + 12; // Account for text length code and other marker
        sample->duration = (MP4Duration)duration;

        // 2-byte length marker
        sample->sample[0] = (stringLength >> 8) & 0xff;
        sample->sample[1] = stringLength & 0xff;

        strncpy( (char *)&(sample->sample[2]), textString, stringLength );

        x = 2 + stringLength;

        // Modifier Length Marker
        sample->sample[x] = 0x00;
        sample->sample[x+1] = 0x00;
        sample->sample[x+2] = 0x00;
        sample->sample[x+3] = 0x0C;

        // Modifier Type Code
        sample->sample[x+4] = 'e';
        sample->sample[x+5] = 'n';
        sample->sample[x+6] = 'c';
        sample->sample[x+7] = 'd';

        // Modifier Value
        sample->sample[x+8] = 0x00;
        sample->sample[x+9] = 0x00;
        sample->sample[x+10] = (256 >> 8) & 0xff;
        sample->sample[x+11] = 256 & 0xff;
    }

    return sample;
}

/**********************************************************************
 * MP4GenerateChapterSample
 **********************************************************************
 * Creates a buffer for a text track sample
 *********************************************************************/
static struct hb_text_sample_s *MP4GenerateChapterSample( hb_mux_object_t * m,
                                                          uint64_t duration,
                                                          int chapter )
{
    // We substract 1 from the chapter number because the chapters start at
    // 1 but our name array starts at 0. We substract another 1 because we're
    // writing the text of the previous chapter mark (when we get the start
    // of chapter 2 we know the duration of chapter 1 & can write its mark).
    hb_chapter_t *chapter_data = hb_list_item( m->job->title->list_chapter,
                                               chapter - 2 );
    char tmp_buffer[1024];
    char *string = tmp_buffer;

    tmp_buffer[0] = '\0';

    if( chapter_data != NULL )
    {
        string = chapter_data->title;
    }

    if( strlen(string) == 0 || strlen(string) >= 1024 )
    {
        snprintf( tmp_buffer, 1023, "Chapter %03i", chapter - 2 );
        string = tmp_buffer;
    }

    return MP4CreateTextSample( string, duration );
}


/**********************************************************************
 * MP4Init
 **********************************************************************
 * Allocates hb_mux_data_t structures, create file and write headers
 *********************************************************************/
static int MP4Init( hb_mux_object_t * m )
{
    hb_job_t   * job   = m->job;
    hb_title_t * title = job->title;

    hb_audio_t    * audio;
    hb_mux_data_t * mux_data;
    int i;
    u_int16_t language_code;

    /* Flags for enabling/disabling tracks in an MP4. */
    typedef enum { TRACK_DISABLED = 0x0, TRACK_ENABLED = 0x1, TRACK_IN_MOVIE = 0x2, TRACK_IN_PREVIEW = 0x4, TRACK_IN_POSTER = 0x8}  track_header_flags;

    if( (audio = hb_list_item(title->list_audio, 0)) != NULL )
    {
        /* Need the sample rate of the first audio track to use as the timescale. */
        m->samplerate = audio->config.out.samplerate;
        audio = NULL;
    }
    else
    {
        m->samplerate = 90000;
    }

    /* Create an empty mp4 file */
    if (job->largeFileSize)
    /* Use 64-bit MP4 file */
    {
        m->file = MP4Create( job->file, MP4_DETAILS_ERROR, MP4_CREATE_64BIT_DATA );
        hb_deep_log( 2, "muxmp4: using 64-bit MP4 formatting.");
    }
    else
    /* Limit MP4s to less than 4 GB */
    {
        m->file = MP4Create( job->file, MP4_DETAILS_ERROR, 0 );
    }

    if (m->file == MP4_INVALID_FILE_HANDLE)
    {
        hb_error("muxmp4.c: MP4Create failed!");
        *job->die = 1;
        return 0;
    }

    /* Video track */
    mux_data      = malloc( sizeof( hb_mux_data_t ) );
    job->mux_data = mux_data;

    /* When using the standard 90000 timescale, QuickTime tends to have
       synchronization issues (audio not playing at the correct speed).
       To workaround this, we use the audio samplerate as the
       timescale */
    if (!(MP4SetTimeScale( m->file, m->samplerate )))
    {
        hb_error("muxmp4.c: MP4SetTimeScale failed!");
        *job->die = 1;
        return 0;
    }

    if( job->vcodec == HB_VCODEC_X264 )
    {
        /* Stolen from mp4creator */
        if(!(MP4SetVideoProfileLevel( m->file, 0x7F )))
        {
            hb_error("muxmp4.c: MP4SetVideoProfileLevel failed!");
            *job->die = 1;
            return 0;
        }

		mux_data->track = MP4AddH264VideoTrack( m->file, m->samplerate,
		        MP4_INVALID_DURATION, job->width, job->height,
		        job->config.h264.sps[1], /* AVCProfileIndication */
		        job->config.h264.sps[2], /* profile_compat */
		        job->config.h264.sps[3], /* AVCLevelIndication */
		        3 );      /* 4 bytes length before each NAL unit */


        MP4AddH264SequenceParameterSet( m->file, mux_data->track,
                job->config.h264.sps, job->config.h264.sps_length );
        MP4AddH264PictureParameterSet( m->file, mux_data->track,
                job->config.h264.pps, job->config.h264.pps_length );

		if( job->h264_level == 30 || job->ipod_atom)
		{
			hb_deep_log( 2, "muxmp4: adding iPod atom");
			AddIPodUUID(m->file, mux_data->track);
		}

        m->init_delay = job->config.h264.init_delay;
    }
    else /* FFmpeg or XviD */
    {
        if(!(MP4SetVideoProfileLevel( m->file, MPEG4_SP_L3 )))
        {
            hb_error("muxmp4.c: MP4SetVideoProfileLevel failed!");
            *job->die = 1;
            return 0;
        }
        mux_data->track = MP4AddVideoTrack( m->file, m->samplerate,
                MP4_INVALID_DURATION, job->width, job->height,
                MP4_MPEG4_VIDEO_TYPE );
        if (mux_data->track == MP4_INVALID_TRACK_ID)
        {
            hb_error("muxmp4.c: MP4AddVideoTrack failed!");
            *job->die = 1;
            return 0;
        }


        /* VOL from FFmpeg or XviD */
        if (!(MP4SetTrackESConfiguration( m->file, mux_data->track,
                job->config.mpeg4.bytes, job->config.mpeg4.length )))
        {
            hb_error("muxmp4.c: MP4SetTrackESConfiguration failed!");
            *job->die = 1;
            return 0;
        }
    }

    // COLR atom for color and gamma correction.
    // Per the notes at:
    //   http://developer.apple.com/quicktime/icefloe/dispatch019.html#colr
    //   http://forum.doom9.org/showthread.php?t=133982#post1090068
    // we say anything that's likely to be HD content is ITU BT.709 and
    // DVD, SD TV & other content is ITU BT.601.  We look at the title height
    // rather than the job height here to get uncropped input dimensions.
    if ( job->title->height >= 720 )
    {
        // we guess that 720p or above is ITU BT.709 HD content
        MP4AddColr(m->file, mux_data->track, 1, 1, 1);
    }
    else
    {
        // ITU BT.601 DVD or SD TV content
        MP4AddColr(m->file, mux_data->track, 6, 1, 6);
    }

    if( job->pixel_ratio )
    {
        /* PASP atom for anamorphic video */
        float width, height;

        width = job->pixel_aspect_width;

        height = job->pixel_aspect_height;

        MP4AddPixelAspectRatio(m->file, mux_data->track, (uint32_t)width, (uint32_t)height);

        MP4SetTrackFloatProperty(m->file, mux_data->track, "tkhd.width", job->width * (width / height));
    }

	/* add the audio tracks */
    for( i = 0; i < hb_list_count( title->list_audio ); i++ )
    {
    	static u_int8_t reserved2[16] = {
    		0x00, 0x00, 0x00, 0x00,
    		0x00, 0x00, 0x00, 0x00,
    		0x00, 0x02, 0x00, 0x10,
    		0x00, 0x00, 0x00, 0x00,
	    };

        audio = hb_list_item( title->list_audio, i );
        mux_data = malloc( sizeof( hb_mux_data_t ) );
        audio->priv.mux_data = mux_data;

        if( audio->config.out.codec == HB_ACODEC_AC3 )
        {
            mux_data->track = MP4AddAC3AudioTrack(
                m->file,
                m->samplerate, 1536, MP4_MPEG4_AUDIO_TYPE );
            MP4SetTrackBytesProperty(
                m->file, mux_data->track,
                "udta.name.value",
                (const u_int8_t*)"Surround", strlen("Surround"));
        } else {
            mux_data->track = MP4AddAudioTrack(
                m->file,
                m->samplerate, 1024, MP4_MPEG4_AUDIO_TYPE );
            MP4SetTrackBytesProperty(
                m->file, mux_data->track,
                "udta.name.value",
                (const u_int8_t*)"Stereo", strlen("Stereo"));

            MP4SetAudioProfileLevel( m->file, 0x0F );
            MP4SetTrackESConfiguration(
                m->file, mux_data->track,
                audio->priv.config.aac.bytes, audio->priv.config.aac.length );

            /* Set the correct number of channels for this track */
            reserved2[9] = (u_int8_t)HB_AMIXDOWN_GET_DISCRETE_CHANNEL_COUNT(audio->config.out.mixdown);
            MP4SetTrackBytesProperty(m->file, mux_data->track, "mdia.minf.stbl.stsd.mp4a.reserved2", reserved2, sizeof(reserved2));

        }
        /* Set the language for this track */
        /* The language is stored as 5-bit text - 0x60 */
        language_code = audio->config.lang.iso639_2[0] - 0x60;   language_code <<= 5;
        language_code |= audio->config.lang.iso639_2[1] - 0x60;  language_code <<= 5;
        language_code |= audio->config.lang.iso639_2[2] - 0x60;
        MP4SetTrackIntegerProperty(m->file, mux_data->track, "mdia.mdhd.language", language_code);


        /* Set the audio track alternate group */
        MP4SetTrackIntegerProperty(m->file, mux_data->track, "tkhd.alternate_group", 1);

        /* If we ever upgrade mpeg4ip, the line above should be replaced with the line below.*/
//        MP4SetTrackIntegerProperty(m->file, mux_data->track, "mdia.minf.stbl.stsd.mp4a.channels",  (u_int16_t)HB_AMIXDOWN_GET_DISCRETE_CHANNEL_COUNT(audio->amixdown));

        if (i == 0) {
            /* Enable the first audio track */
            MP4SetTrackIntegerProperty(m->file, mux_data->track, "tkhd.flags", (TRACK_ENABLED | TRACK_IN_MOVIE));
        }
        else
            /* Disable the other audio tracks so QuickTime doesn't play
               them all at once. */
        {
            MP4SetTrackIntegerProperty(m->file, mux_data->track, "tkhd.flags", (TRACK_DISABLED | TRACK_IN_MOVIE));
            hb_deep_log( 2, "muxp4: disabled extra audio track %i", mux_data->track-1);
        }

    }

	if (job->chapter_markers)
    {
        /* add a text track for the chapters. We add the 'chap' atom to track
           one which is usually the video track & should never be disabled.
           The Quicktime spec says it doesn't matter which media track the
           chap atom is on but it has to be an enabled track. */
        MP4TrackId textTrack;
        textTrack = MP4AddChapterTextTrack(m->file, 1);

        m->chapter_track = textTrack;
        m->chapter_duration = 0;
        m->current_chapter = job->chapter_start;
    }

    /* Add encoded-by metadata listing version and build date */
    char *tool_string;
    tool_string = (char *)malloc(80);
    snprintf( tool_string, 80, "HandBrake %s %i", HB_VERSION, HB_BUILD);
    MP4SetMetadataTool(m->file, tool_string);
    free(tool_string);

    return 0;
}

static int MP4Mux( hb_mux_object_t * m, hb_mux_data_t * mux_data,
                   hb_buffer_t * buf )
{
    hb_job_t * job = m->job;
    int64_t duration;
    int64_t offset = 0;

    if( mux_data == job->mux_data )
    {
        /* Video */

        // if there are b-frames compute the render offset
        // (we'll need it for both the video frame & the chapter track)
        if ( m->init_delay )
        {
            offset = ( buf->start + m->init_delay ) * m->samplerate / 90000 -
                     m->sum_dur;
        }
        /* Add the sample before the new frame.
           It is important that this be calculated prior to the duration
           of the new video sample, as we want to sync to right after it.
           (This is because of how durations for text tracks work in QT) */
        if( job->chapter_markers && buf->new_chap )
        {
            struct hb_text_sample_s *sample;

            // this chapter is postioned by writing out the previous chapter.
            // the duration of the previous chapter is the duration up to but
            // not including the current frame minus the duration of all
            // chapters up to the previous.
            duration = m->sum_dur - m->chapter_duration + offset;
            if ( duration <= 0 )
            {
                /* The initial & final chapters can have very short durations
                 * (less than the error in our total duration estimate) so
                 * the duration calc above can result in a negative number.
                 * when this happens give the chapter a short duration (1/3
                 * of an ntsc frame time). */
                duration = 1000 * m->samplerate / 90000;
            }

            sample = MP4GenerateChapterSample( m, duration, buf->new_chap );

            if( !MP4WriteSample(m->file,
                                m->chapter_track,
                                sample->sample,
                                sample->length,
                                sample->duration,
                                0, true) )
            {
                hb_error("Failed to write to output file, disk full?");
                *job->die = 1;
            }
            free(sample);
            m->current_chapter = buf->new_chap;
            m->chapter_duration += duration;
        }

        // since we're changing the sample rate we need to keep track of
        // the truncation bias so that the audio and video don't go out
        // of sync. m->sum_dur_in is the sum of the input durations so far.
        // m->sum_dur is the sum of the output durations. Their difference
        // (in output sample rate units) is the accumulated truncation bias.
        int64_t bias = ( m->sum_dur_in * m->samplerate / 90000 ) - m->sum_dur;
        int64_t dur_in = buf->stop - buf->start;
        duration = dur_in * m->samplerate / 90000 + bias;
        if ( duration <= 0 )
        {
            /* We got an illegal mp4/h264 duration. This shouldn't
               be possible and usually indicates a bug in the upstream code.
               Complain in the hope that someone will go find the bug but
               try to fix the error so that the file will still be playable. */
            hb_log("MP4Mux: illegal duration %lld, bias %lld, start %lld (%lld),"
                   "stop %lld (%lld), sum_dur %lld",
                   duration, bias, buf->start * m->samplerate / 90000, buf->start,
                   buf->stop * m->samplerate / 90000, buf->stop, m->sum_dur );
            /* we don't know when the next frame starts so we can't pick a
               valid duration for this one so we pick something "short"
               (roughly 1/3 of an NTSC frame time) and rely on the bias calc
               for the next frame to correct things (a duration underestimate
               just results in a large bias on the next frame). */
            duration = 1000 * m->samplerate / 90000;
        }
        m->sum_dur += duration;
        m->sum_dur_in += dur_in;
    }
    else
    {
        /* Audio */
        duration = MP4_INVALID_DURATION;
    }

    // Here's where the sample actually gets muxed.
    if( !MP4WriteSample( m->file,
                         mux_data->track,
                         buf->data,
                         buf->size,
                         duration,
                         offset,
                         ((buf->frametype & HB_FRAME_KEY) != 0) ) )
    {
        hb_error("Failed to write to output file, disk full?");
        *job->die = 1;
    }

    return 0;
}

static int MP4End( hb_mux_object_t * m )
{
    hb_job_t   * job   = m->job;

    /* Write our final chapter marker */
    if( m->job->chapter_markers )
    {
        int64_t duration = m->sum_dur - m->chapter_duration;
        /* The final chapter can have a very short duration - if it's less
         * than a second just skip it. */
        if ( duration >= m->samplerate )
        {

            struct hb_text_sample_s *sample = MP4GenerateChapterSample( m, duration,
                                                    m->current_chapter + 1 );
            if( ! MP4WriteSample(m->file, m->chapter_track, sample->sample,
                                 sample->length, sample->duration, 0, true) )
            {
                hb_error("Failed to write to output file, disk full?");
                *job->die = 1;
            }
            free(sample);
        }
    }

    if (job->areBframes)
    {
           // Insert track edit to get A/V back in sync.  The edit amount is
           // the init_delay.
           int64_t edit_amt = m->init_delay * m->samplerate / 90000;
           MP4AddTrackEdit(m->file, 1, MP4_INVALID_EDIT_ID, edit_amt,
                           MP4GetTrackDuration(m->file, 1), 0);
            if ( m->job->chapter_markers )
            {
                // apply same edit to chapter track to keep it in sync with video
                MP4AddTrackEdit(m->file, m->chapter_track, MP4_INVALID_EDIT_ID,
                                edit_amt,
                                MP4GetTrackDuration(m->file, m->chapter_track), 0);
            }
     }

    MP4Close( m->file );

    if ( job->mp4_optimize )
    {
        hb_log( "muxmp4: optimizing file" );
        char filename[1024]; memset( filename, 0, 1024 );
        snprintf( filename, 1024, "%s.tmp", job->file );
        MP4Optimize( job->file, filename, MP4_DETAILS_ERROR );
        remove( job->file );
        rename( filename, job->file );
    }

    return 0;
}

hb_mux_object_t * hb_mux_mp4_init( hb_job_t * job )
{
    hb_mux_object_t * m = calloc( sizeof( hb_mux_object_t ), 1 );
    m->init      = MP4Init;
    m->mux       = MP4Mux;
    m->end       = MP4End;
    m->job       = job;
    return m;
}