vgmstream/src/coding/mpeg_decoder.c

600 lines
22 KiB
C
Raw Normal View History

#include "coding.h"
#include "../util.h"
#include "../vgmstream.h"
#ifdef VGM_USE_MPEG
#include <mpg123.h>
#include "mpeg_decoder.h"
/* TODO list for custom decoder
* - don't force channel param and get them from frame headers for some types (for MPEG_STANDARD)
* - use one stream per channel and advance streams as channels are done in case of streams like 2ch+1ch+1ch+2ch (not seen)
* (would also need to change sample_buffer copy)
* - improve validation of channels/samples_per_frame between streams
* - improve decoded samples to sample buffer copying (very picky with sizes)
* - use mpg123 stream_buffer, with flags per stream, and call copy to sample_buffer when all streams have some samples
* (so it could handle interleaved VBR frames).
* - AHX type 8 encryption
* - test encoder delays
* - improve error handling
*/
/* mostly arbitrary max values */
#define MPEG_DATA_BUFFER_SIZE 0x1000
#define MPEG_MAX_CHANNELS 16
#define MPEG_MAX_STREAM_FRAMES 10
static mpg123_handle * init_mpg123_handle();
static void decode_mpeg_standard(VGMSTREAMCHANNEL *stream, mpeg_codec_data * data, sample * outbuf, int32_t samples_to_do, int channels);
static void decode_mpeg_custom(VGMSTREAM * vgmstream, mpeg_codec_data * data, sample * outbuf, int32_t samples_to_do, int channels);
static void decode_mpeg_custom_stream(VGMSTREAMCHANNEL *stream, mpeg_codec_data * data, mpg123_handle *m, int channels, int num_stream);
/* Inits regular MPEG */
mpeg_codec_data *init_mpeg_codec_data(STREAMFILE *streamfile, off_t start_offset, coding_t *coding_type, int channels) {
mpeg_codec_data *data = NULL;
/* init codec */
data = calloc(1,sizeof(mpeg_codec_data));
if (!data) goto fail;
data->buffer_size = MPEG_DATA_BUFFER_SIZE;
data->buffer = calloc(sizeof(uint8_t), data->buffer_size);
if (!data->buffer) goto fail;
2017-02-18 18:27:21 +01:00
data->m = init_mpg123_handle();
if (!data->m) goto fail;
/* check format */
{
2017-02-18 18:27:21 +01:00
mpg123_handle *main_m = data->m;
off_t read_offset = 0;
int rc;
long sample_rate_per_frame;
int channels_per_frame, encoding;
size_t samples_per_frame;
struct mpg123_frameinfo mi;
2017-02-18 18:27:21 +01:00
/* read first frame(s) */
do {
size_t bytes_done;
if (read_streamfile(data->buffer, start_offset+read_offset, data->buffer_size, streamfile) != data->buffer_size)
goto fail;
read_offset+=1;
rc = mpg123_decode(main_m, data->buffer,data->buffer_size, NULL,0, &bytes_done);
if (rc != MPG123_OK && rc != MPG123_NEW_FORMAT && rc != MPG123_NEED_MORE) {
VGM_LOG("MPEG: unable to set up mpg123 @ 0x%08lx to 0x%08lx\n", start_offset, read_offset);
goto fail; //handle MPG123_DONE?
}
if (read_offset > 0x5000) { /* don't hang in some incorrectly detected formats */
VGM_LOG("MPEG: unable to find mpeg data @ 0x%08lx to 0x%08lx\n", start_offset, read_offset);
goto fail;
}
2017-02-18 18:27:21 +01:00
} while (rc != MPG123_NEW_FORMAT);
/* check first frame header and validate */
rc = mpg123_getformat(main_m,&sample_rate_per_frame,&channels_per_frame,&encoding);
if (rc != MPG123_OK) goto fail;
mpg123_info(main_m,&mi);
2017-02-18 18:27:21 +01:00
if (encoding != MPG123_ENC_SIGNED_16)
goto fail;
if (sample_rate_per_frame != mi.rate)
goto fail;
if ((channels != -1 && channels_per_frame != channels))
goto fail;
switch(mi.layer) {
case 1: *coding_type = coding_MPEG_layer1; break;
case 2: *coding_type = coding_MPEG_layer2; break;
case 3: *coding_type = coding_MPEG_layer3; break;
default: goto fail;
}
if (mi.layer == 1)
samples_per_frame = 384;
else if (mi.layer == 2)
samples_per_frame = 1152;
else if (mi.layer == 3 && mi.version == MPG123_1_0) //MP3
samples_per_frame = 1152;
else if (mi.layer == 3)
samples_per_frame = 576;
else goto fail;
data->channels_per_frame = channels_per_frame;
data->samples_per_frame = samples_per_frame;
if (channels_per_frame != channels)
goto fail;
2017-02-18 18:27:21 +01:00
/* reinit, to ignore the reading we've done so far */
mpg123_open_feed(main_m);
}
return data;
fail:
free_mpeg(data);
return NULL;
}
/* Init custom MPEG, with given type and config. */
mpeg_codec_data *init_mpeg_custom_codec_data(STREAMFILE *streamFile, off_t start_offset, coding_t *coding_type, int channels, mpeg_custom_t type, mpeg_custom_config *config) {
mpeg_codec_data *data = NULL;
int stream_frames = 1;
int i, ok;
/* init codec */
data = calloc(1,sizeof(mpeg_codec_data));
if (!data) goto fail;
data->buffer_size = MPEG_DATA_BUFFER_SIZE;
data->buffer = calloc(sizeof(uint8_t), data->buffer_size);
if (!data->buffer) goto fail;
/* keep around to decode */
data->custom = 1;
data->type = type;
memcpy(&data->config, config, sizeof(mpeg_custom_config));
data->config.channels = channels;
/* init per subtype */
switch(data->type) {
case MPEG_EAL31:
case MPEG_EAL32P:
case MPEG_EAL32S: ok = 0; break; //ok = mpeg_custom_setup_init_ealayer3(streamFile, start_offset, data, coding_type); break;
default: ok = mpeg_custom_setup_init_default(streamFile, start_offset, data, coding_type); break;
}
if (!ok)
goto fail;
if (channels <= 0 || channels > MPEG_MAX_CHANNELS) goto fail;
if (channels < data->channels_per_frame) goto fail;
/* init stream decoders (separate as MPEG frames may need N previous frames from their stream to decode) */
data->ms_size = channels / data->channels_per_frame;
data->ms = calloc(sizeof(mpg123_handle *), data->ms_size);
for (i=0; i < data->ms_size; i++) {
data->ms[i] = init_mpg123_handle();
if (!data->ms[i]) goto fail;
}
if (stream_frames > MPEG_MAX_STREAM_FRAMES) goto fail;
/* init stream buffer, big enough for one stream and N frames at a time (will be copied to sample buffer) */
data->stream_buffer_size = sizeof(sample) * data->channels_per_frame * stream_frames * data->samples_per_frame;
data->stream_buffer = calloc(sizeof(uint8_t), data->stream_buffer_size);
if (!data->stream_buffer) goto fail;
/* init sample buffer, big enough for all streams/channels and N frames at a time */
data->sample_buffer_size = sizeof(sample) * channels * stream_frames * data->samples_per_frame;
data->sample_buffer = calloc(sizeof(uint8_t), data->sample_buffer_size);
if (!data->sample_buffer) goto fail;
/* write output */
config->interleave = data->config.interleave; /* for FSB */
2017-02-18 18:27:21 +01:00
return data;
2017-02-18 18:27:21 +01:00
fail:
free_mpeg(data);
return NULL;
}
static mpg123_handle * init_mpg123_handle() {
mpg123_handle *m = NULL;
int rc;
/* inits a new mpg123 handle */
m = mpg123_new(NULL,&rc);
if (rc == MPG123_NOT_INITIALIZED) {
/* inits the library if needed */
if (mpg123_init() != MPG123_OK)
goto fail;
m = mpg123_new(NULL,&rc);
if (rc != MPG123_OK) goto fail;
2017-02-18 18:27:21 +01:00
} else if (rc != MPG123_OK) {
goto fail;
}
mpg123_param(m,MPG123_REMOVE_FLAGS,MPG123_GAPLESS,0.0); /* wonky support */
mpg123_param(m,MPG123_RESYNC_LIMIT, -1, 0x10000); /* should be enough */
2017-02-18 18:27:21 +01:00
if (mpg123_open_feed(m) != MPG123_OK) {
goto fail;
}
2017-02-18 18:27:21 +01:00
return m;
fail:
2017-02-18 18:27:21 +01:00
mpg123_delete(m);
return NULL;
}
2017-02-18 18:27:21 +01:00
/************/
/* DECODERS */
/************/
void decode_mpeg(VGMSTREAM * vgmstream, sample * outbuf, int32_t samples_to_do, int channels) {
mpeg_codec_data * data = (mpeg_codec_data *) vgmstream->codec_data;
if (!data->custom) {
decode_mpeg_standard(&vgmstream->ch[0], data, outbuf, samples_to_do, channels);
} else {
decode_mpeg_custom(vgmstream, data, outbuf, samples_to_do, channels);
}
2017-02-18 18:27:21 +01:00
}
/**
* Decode anything mpg123 can.
* Feeds raw data and extracts decoded samples as needed.
*/
static void decode_mpeg_standard(VGMSTREAMCHANNEL *stream, mpeg_codec_data * data, sample * outbuf, int32_t samples_to_do, int channels) {
int samples_done = 0;
mpg123_handle *m = data->m;
while (samples_done < samples_to_do) {
size_t bytes_done;
int rc;
/* read more raw data */
if (!data->buffer_full) {
data->bytes_in_buffer = read_streamfile(data->buffer,stream->offset,data->buffer_size,stream->streamfile);
/* end of stream, fill rest with 0s */
if (!data->bytes_in_buffer) {
memset(outbuf + samples_done * channels, 0, (samples_to_do - samples_done) * sizeof(sample));
break;
}
data->buffer_full = 1;
data->buffer_used = 0;
stream->offset += data->bytes_in_buffer;
}
/* feed new raw data to the decoder if needed, copy decoded results to output */
if (!data->buffer_used) {
2017-02-18 18:27:21 +01:00
rc = mpg123_decode(m,
data->buffer,data->bytes_in_buffer,
(unsigned char *)(outbuf+samples_done*channels),
(samples_to_do-samples_done)*sizeof(sample)*channels,
&bytes_done);
data->buffer_used = 1;
}
else {
2017-02-18 18:27:21 +01:00
rc = mpg123_decode(m,
NULL,0,
(unsigned char *)(outbuf+samples_done*channels),
(samples_to_do-samples_done)*sizeof(sample)*channels,
&bytes_done);
}
/* not enough raw data, request more */
if (rc == MPG123_NEED_MORE) {
data->buffer_full = 0;
}
/* update copied samples */
samples_done += bytes_done/sizeof(sample)/channels;
}
}
/**
* Decode custom MPEG, allowing support for: single frames, interleave, mutant frames, multiple streams
* (1 frame = 1/2ch so Nch = 2ch*N/2 or 1ch*N or 2ch+1ch+2ch+...), etc.
*
* Decodes samples per each stream and muxes them into a single internal buffer before copying to outbuf
* (to make sure channel samples are orderly copied between decode_mpeg calls).
* decode_mpeg_custom_stream does the main decoding, while this handles layout and copying samples to output.
*/
static void decode_mpeg_custom(VGMSTREAM * vgmstream, mpeg_codec_data * data, sample * outbuf, int32_t samples_to_do, int channels) {
int samples_done = 0, bytes_max, bytes_to_copy;
while (samples_done < samples_to_do) {
if (data->bytes_used_in_sample_buffer < data->bytes_in_sample_buffer) {
/* copy remaining samples */
bytes_to_copy = data->bytes_in_sample_buffer - data->bytes_used_in_sample_buffer;
bytes_max = (samples_to_do - samples_done) * sizeof(sample) * channels;
if (bytes_to_copy > bytes_max)
bytes_to_copy = bytes_max;
memcpy((uint8_t*)(outbuf+samples_done*channels), data->sample_buffer + data->bytes_used_in_sample_buffer, bytes_to_copy);
/* update samples copied */
data->bytes_used_in_sample_buffer += bytes_to_copy;
samples_done += bytes_to_copy / sizeof(sample) / channels;
}
else {
/* fill the internal sample buffer */
int i;
data->bytes_in_sample_buffer = 0;
data->bytes_used_in_sample_buffer = 0;
/* Handle offsets depending on the data layout (may only use half VGMSTREAMCHANNELs with 2ch streams)
* With multiple offsets it's expected offsets are set up pointing to the first frame of each stream. */
for (i=0; i < data->ms_size; i++) {
switch(data->type) {
//case MPEG_LYN:
case MPEG_FSB:
case MPEG_XVAG:
case MPEG_P3D:
/* multiple offsets, decodes 1 frame per stream until reaching interleave/block_size and skips it */
decode_mpeg_custom_stream(&vgmstream->ch[i], data, data->ms[i], channels, i);
break;
//case MPEG_EA: //?
case MPEG_AWC:
/* consecutive streams: multiple offsets, decodes 1 frame per stream */
decode_mpeg_custom_stream(&vgmstream->ch[i], data, data->ms[i], channels, i);
break;
default:
/* N frames: single offset, decodes all N frames per stream (sample buffer must be big enough for N) */
decode_mpeg_custom_stream(&vgmstream->ch[0], data, data->ms[i], channels, i);
break;
}
}
/* discard (for looping): 'remove' decoded samples from the buffer */
if (data->samples_to_discard) {
size_t bytes_to_discard = data->samples_to_discard * sizeof(sample) * channels;
/* 'remove' all buffer at most */
if (bytes_to_discard > data->bytes_in_sample_buffer)
bytes_to_discard = data->bytes_in_sample_buffer;
/* pretend the samples were used up and readjust discard */
data->bytes_used_in_sample_buffer = bytes_to_discard;
data->samples_to_discard -= bytes_to_discard / sizeof(sample) / channels;;
}
}
}
}
/* Decodes frames from a stream and muxes samples into a intermediate buffer and moves the stream offsets. */
static void decode_mpeg_custom_stream(VGMSTREAMCHANNEL *stream, mpeg_codec_data * data, mpg123_handle *m, int channels, int num_stream) {
size_t bytes_done = 0;
size_t stream_size = get_streamfile_size(stream->streamfile);
int rc, ok;
/* decode samples from one full-frame (as N data-frames = 1 full-frame) before exiting (to orderly copy to sample buffer) */
do {
//VGM_LOG("MPEG: new step of stream %i @ 0x%08lx\n", num_stream, stream->offset);
/* extra EOF check for edge cases when the caller tries to read more samples than possible */
if (stream->offset >= stream_size) {
memset(data->stream_buffer, 0, data->stream_buffer_size);
bytes_done = data->stream_buffer_size;
break; /* continue with other streams */
}
/* read more raw data */
if (!data->buffer_full) {
//VGM_LOG("MPEG: reading more raw data\n");
switch(data->type) {
case MPEG_EAL31:
case MPEG_EAL32P:
case MPEG_EAL32S: ok = 0; break; //ok = mpeg_custom_parse_frame_ealayer3(stream, data); break;
case MPEG_AHX: ok = mpeg_custom_parse_frame_ahx(stream, data); break;
default: ok = mpeg_custom_parse_frame_default(stream, data); break;
}
/* error/EOF, mpg123 can resync in some cases but custom MPEGs wouldn't need that */
if (!ok || !data->bytes_in_buffer) {
VGM_LOG("MPEG: cannot parse frame @ around %lx\n",stream->offset);
memset(data->stream_buffer, 0, data->stream_buffer_size);
bytes_done = data->stream_buffer_size;
break; /* continue with other streams */
}
//VGM_LOG("MPEG: read results: bytes_in_buffer=0x%x, new offset off=%lx\n", data->bytes_in_buffer, stream->offset);
data->buffer_full = 1;
data->buffer_used = 0;
}
#if 0
//TODO: in case of EALayer3 with "PCM flag" must put them in buffer
if (ea_pcm_flag) {
/* write some samples to data->stream_buffer *before* decoding this frame */
bytes_done += read_streamfile(data->stream_buffer,offset,num_pcm_samples,stream->streamfile);
}
#endif
#if 0
//TODO: FSB sometimes has garbage in the first frames, not sure why/when, no apparent patern
if (data->custom_type == MPEG_FSB && stream->offset == stream->channel_start_offset) { /* first frame */
VGM_LOG("MPEG: skip first frame @ %x - %x\n", stream->offset, stream->channel_start_offset);
data->buffer_full = 0;
memset(data->stream_buffer, 0, data->stream_buffer_size);
bytes_done = data->stream_buffer_size;
break;
}
#endif
/* feed new raw data to the decoder if needed, copy decoded results to frame buffer output */
if (!data->buffer_used) {
//VGM_LOG("MPEG: feed new data and get samples \n");
rc = mpg123_decode(m,
data->buffer, data->bytes_in_buffer,
(unsigned char *)data->stream_buffer /*+bytes_done*/, data->stream_buffer_size,
&bytes_done);
data->buffer_used = 1;
}
else {
//VGM_LOG("MPEG: get samples from old data\n");
rc = mpg123_decode(m,
NULL,0,
(unsigned char *)data->stream_buffer /*+bytes_done*/, data->stream_buffer_size,
&bytes_done);
}
/* not enough raw data, request more */
if (rc == MPG123_NEED_MORE) {
//VGM_LOG("MPEG: need more raw data to get samples\n");
/* (apparently mpg123 can give bytes and request more at the same time and may mess up some calcs, when/how? */
VGM_ASSERT(bytes_done > 0, "MPEG: bytes done but decoder requests more data\n");
data->buffer_full = 0;
continue;
}
//VGM_LOG("MPEG: got samples, bytes_done=0x%x (fsbs=0x%x)\n", bytes_done, data->stream_buffer_size);
break;
} while (1);
/* copy decoded full-frame to intermediate sample buffer, muxing channels
* (ex stream1: ch1s1 ch1s2, stream2: ch2s1 ch2s2 > ch1s1 ch2s1 ch1s2 ch2s2) */
{
size_t samples_done;
size_t sz = sizeof(sample);
int channels_f = data->channels_per_frame;
int fch, i;
samples_done = bytes_done / sz / channels_f;
for (fch = 0; fch < channels_f; fch++) { /* channels inside the frame */
for (i = 0; i < samples_done; i++) { /* decoded samples */
off_t in_offset = sz*i*channels_f + sz*fch;
off_t out_offset = sz*i*channels + sz*(num_stream*channels_f + fch);
memcpy(data->sample_buffer + out_offset, data->stream_buffer + in_offset, sz);
}
}
data->bytes_in_sample_buffer += bytes_done;
}
}
2017-02-18 18:27:21 +01:00
/*********/
/* UTILS */
/*********/
void free_mpeg(mpeg_codec_data *data) {
if (!data)
return;
if (!data->custom) {
mpg123_delete(data->m);
}
else {
int i;
for (i=0; i < data->ms_size; i++) {
mpg123_delete(data->ms[i]);
}
free(data->ms);
free(data->stream_buffer);
free(data->sample_buffer);
}
free(data->buffer);
free(data);
/* The astute reader will note that a call to mpg123_exit is never
* made. While is is evilly breaking our contract with mpg123, it
* doesn't actually do anything except set the "initialized" flag
* to 0. And if we exit we run the risk of turning it off when
* someone else in another thread is using it. */
}
void reset_mpeg(VGMSTREAM *vgmstream) {
off_t input_offset;
mpeg_codec_data *data = vgmstream->codec_data;
/* reset multistream */ //todo check if stream offsets are properly reset
if (!data->custom) {
/* input_offset is ignored as we can assume it will be 0 for a seek to sample 0 */
mpg123_feedseek(data->m,0,SEEK_SET,&input_offset);
}
else {
int i;
for (i=0; i < data->ms_size; i++) {
mpg123_feedseek(data->ms[i],0,SEEK_SET,&input_offset);
}
data->bytes_in_sample_buffer = 0;
data->bytes_used_in_sample_buffer = 0;
/* initial delay */
data->samples_to_discard = data->skip_samples;
}
}
void seek_mpeg(VGMSTREAM *vgmstream, int32_t num_sample) {
off_t input_offset;
mpeg_codec_data *data = vgmstream->codec_data;
/* seek multistream */
if (!data->custom) {
mpg123_feedseek(data->m, num_sample,SEEK_SET,&input_offset);
if (vgmstream->loop_ch)
vgmstream->loop_ch[0].offset = vgmstream->loop_ch[0].channel_start_offset + input_offset;
}
else {
int i;
/* re-start from 0 */
for (i=0; i < data->ms_size; i++) {
mpg123_feedseek(data->ms[i],0,SEEK_SET,&input_offset);
if (vgmstream->loop_ch)
vgmstream->loop_ch[i].offset = vgmstream->loop_ch[i].channel_start_offset;
}
data->bytes_in_sample_buffer = 0;
data->bytes_used_in_sample_buffer = 0;
/* manually discard samples, since we don't really know the correct offset */
data->samples_to_discard = num_sample;
data->samples_to_discard += data->skip_samples;
}
data->buffer_full = 0;
data->buffer_used = 0;
}
long mpeg_bytes_to_samples(long bytes, const mpeg_codec_data *data) {
/* if not found just return 0 and expect to fail (if used for num_samples) */
if (!data->custom) {
struct mpg123_frameinfo mi;
mpg123_handle *m = data->m;
if (m == NULL || MPG123_OK != mpg123_info(m, &mi))
return 0;
/* We would need to read all VBR frames headers to count samples */
if (mi.vbr != MPG123_CBR) //maybe abr_rate could be used to get an approx
return 0;
return (int64_t)bytes * mi.rate * 8 / (mi.bitrate * 1000);
}
else {
return 0; /* a bit too complex for what is worth */
}
}
/* disables/enables stderr output, useful for MPEG known to contain recoverable errors */
void mpeg_set_error_logging(mpeg_codec_data * data, int enable) {
if (!data->custom) {
mpg123_param(data->m, MPG123_ADD_FLAGS, MPG123_QUIET, !enable);
}
else {
int i;
for (i=0; i < data->ms_size; i++) {
mpg123_param(data->ms[i], MPG123_ADD_FLAGS, MPG123_QUIET, !enable);
}
}
}
#endif