int quicktime_set_video_position(quicktime_t *file, int64_t frame, int track)
{
int64_t offset, chunk_sample, chunk;
quicktime_trak_t *trak;
if(track >= file->total_vtracks)
{
fprintf(stderr,
"quicktime_set_video_position: frame=%lld track=%d >= file->total_vtracks %d\n",
frame,
track,
file->total_vtracks);
track = file->total_vtracks - 1;
}
if(track < file->total_vtracks && track >= 0)
{
trak = file->vtracks[track].track;
file->vtracks[track].current_position = frame;
quicktime_chunk_of_sample(&chunk_sample, &chunk, trak, frame);
file->vtracks[track].current_chunk = chunk;
offset = quicktime_sample_to_offset(file, trak, frame);
quicktime_set_position(file, offset);
}
return 0;
}
long quicktime_read_audio(quicktime_t *file,
char *audio_buffer, long samples, int track)
{
quicktime_audio_map_t *track_map = &file->atracks[track];
quicktime_trak_t *trak = track_map->track;
int64_t position, chunk, chunk_sample;
long ret, bytes, chunk_offset, chunk_len;
int result = 0;
position = file->atracks[track].current_position;
quicktime_chunk_of_sample(&chunk_sample, &chunk, trak, position);
ret = 0;
while( samples > 0 ) {
int64_t offset = quicktime_sample_to_offset(file, trak, position);
quicktime_set_position(file, offset);
chunk_offset = position - chunk_sample;
chunk_len = quicktime_chunk_samples(trak, chunk) - chunk_offset;
if( chunk_len > samples ) chunk_len = samples;
else ++chunk;
chunk_sample = (position += chunk_len);
bytes = quicktime_samples_to_bytes(trak, chunk_len);
result = !quicktime_read_data(file, &audio_buffer[ret], bytes);
if( result ) break;
ret += bytes;
samples -= chunk_len;
}
//printf("quicktime_read_audio 5\n");
track_map->current_position = position;
track_map->current_chunk = chunk;
return !result ? ret : 0;
}
int quicktime_set_video_position(quicktime_t *file, long frame, int track)
{
long offset, chunk_sample, chunk;
quicktime_trak_t *trak;
if(file->total_vtracks)
{
trak = file->vtracks[track].track;
file->vtracks[track].current_position = frame;
quicktime_chunk_of_sample(&chunk_sample, &chunk, trak, frame);
file->vtracks[track].current_chunk = chunk;
offset = quicktime_sample_to_offset(trak, frame);
quicktime_set_position(file, offset);
/*quicktime_update_positions(file); */
}
return 0;
}
int quicktime_set_audio_position(quicktime_t *file, int64_t sample, int track)
{
int64_t offset, chunk_sample, chunk;
quicktime_trak_t *trak;
if(track < file->total_atracks)
{
trak = file->atracks[track].track;
file->atracks[track].current_position = sample;
quicktime_chunk_of_sample(&chunk_sample, &chunk, trak, sample);
file->atracks[track].current_chunk = chunk;
offset = quicktime_sample_to_offset(file, trak, sample);
quicktime_set_position(file, offset);
}
else
fprintf(stderr, "quicktime_set_audio_position: track >= file->total_atracks\n");
return 0;
}