vgmstream/src/meta/ffmpeg.c
2018-08-19 19:09:37 +02:00

125 lines
3.6 KiB
C

#include "meta.h"
#include "../coding/coding.h"
#ifdef VGM_USE_FFMPEG
static int read_pos_file(uint8_t * buf, size_t bufsize, STREAMFILE *streamFile);
/**
* Generic init FFmpeg and vgmstream for any file supported by FFmpeg.
* Called by vgmstream when trying to identify the file type (if the player allows it).
*/
VGMSTREAM * init_vgmstream_ffmpeg(STREAMFILE *streamFile) {
return init_vgmstream_ffmpeg_offset( streamFile, 0, streamFile->get_size(streamFile) );
}
VGMSTREAM * init_vgmstream_ffmpeg_offset(STREAMFILE *streamFile, uint64_t start, uint64_t size) {
VGMSTREAM *vgmstream = NULL;
int loop_flag = 0;
int32_t loop_start = 0, loop_end = 0, num_samples = 0;
int total_subsongs, target_subsong = streamFile->stream_index;
/* init ffmpeg */
ffmpeg_codec_data *data = init_ffmpeg_offset(streamFile, start, size);
if (!data) return NULL;
total_subsongs = data->streamCount;
if (target_subsong == 0) target_subsong = 1;
if (target_subsong < 0 || target_subsong > total_subsongs || total_subsongs < 1) goto fail;
/* try to get .pos data */
{
uint8_t posbuf[4+4+4];
if ( read_pos_file(posbuf, 4+4+4, streamFile) ) {
loop_start = get_32bitLE(posbuf+0);
loop_end = get_32bitLE(posbuf+4);
loop_flag = 1; /* incorrect looping will be validated outside */
/* FFmpeg can't always determine totalSamples correctly so optionally load it (can be 0/NULL)
* won't crash and will output silence if no loop points and bigger than actual stream's samples */
num_samples = get_32bitLE(posbuf+8);
}
}
/* build VGMSTREAM */
vgmstream = allocate_vgmstream(data->channels, loop_flag);
if (!vgmstream) goto fail;
vgmstream->sample_rate = data->sampleRate;
vgmstream->meta_type = meta_FFMPEG;
vgmstream->coding_type = coding_FFmpeg;
vgmstream->codec_data = data;
vgmstream->layout_type = layout_none;
if (!num_samples) {
num_samples = data->totalSamples;
}
vgmstream->num_samples = num_samples;
if (loop_flag) {
vgmstream->loop_start_sample = loop_start;
vgmstream->loop_end_sample = loop_end;
}
/* this may happen for some streams if FFmpeg can't determine it (ex. AAC) */
if (vgmstream->num_samples <= 0)
goto fail;
return vgmstream;
fail:
free_ffmpeg(data);
if (vgmstream) {
vgmstream->codec_data = NULL;
close_vgmstream(vgmstream);
}
return NULL;
}
/**
* open file containing looping data and copy to buffer
*
* returns true if found and copied
*/
int read_pos_file(uint8_t * buf, size_t bufsize, STREAMFILE *streamFile) {
char posname[PATH_LIMIT];
char filename[PATH_LIMIT];
/*size_t bytes_read;*/
STREAMFILE * streamFilePos= NULL;
streamFile->get_name(streamFile,filename,sizeof(filename));
if (strlen(filename)+4 > sizeof(posname)) goto fail;
/* try to open a posfile using variations: "(name.ext).pos" */
{
strcpy(posname, filename);
strcat(posname, ".pos");
streamFilePos = streamFile->open(streamFile,posname,STREAMFILE_DEFAULT_BUFFER_SIZE);
if (streamFilePos) goto found;
goto fail;
}
found:
//if (get_streamfile_size(streamFilePos) != bufsize) goto fail;
/* allow pos files to be of different sizes in case of new features, just fill all we can */
memset(buf, 0, bufsize);
read_streamfile(buf, 0, bufsize, streamFilePos);
close_streamfile(streamFilePos);
return 1;
fail:
if (streamFilePos) close_streamfile(streamFilePos);
return 0;
}
#endif