cog/Frameworks/vgmstream/vgmstream/src/meta/ogg_opus.c

187 lines
6.7 KiB
C

#include "meta.h"
#include "../coding/coding.h"
static int get_ogg_page_size(STREAMFILE* sf, off_t page_offset, off_t *out_data_offset, size_t *out_page_size);
static int ogg_get_num_samples(STREAMFILE* sf, off_t start_offset);
/* Ogg Opus - standard Opus with optional looping comments [The Pillars of Earth (PC), Monster Boy and the Cursed Kingdom (Switch)] */
VGMSTREAM* init_vgmstream_ogg_opus(STREAMFILE* sf) {
VGMSTREAM* vgmstream = NULL;
off_t start_offset, data_offset = 0;
size_t page_size = 0;
int loop_flag, channel_count, original_rate;
int loop_start = 0, loop_end = 0;
/* checks */
if (!is_id32be(0x00,sf, "OggS"))
goto fail;
/* .opus: standard, .lopus: fake extension for plugins
* .ogg: less common, .logg: same
* .bgm: Utawarerumono: Mask of Truth (PC) */
if (!check_extensions(sf, "opus,lopus,ogg,logg,bgm"))
goto fail;
/* see: https://tools.ietf.org/html/rfc7845.html */
start_offset = 0x00;
/* parse 1st page: opus head */
if (!get_ogg_page_size(sf, start_offset, &data_offset, &page_size))
goto fail;
if (!is_id32be(data_offset+0x00,sf, "Opus") ||
!is_id32be(data_offset+0x04,sf, "Head"))
goto fail;
/* 0x01: version 1, fixed */
channel_count = read_u8(data_offset+0x09,sf);
/* 0x0A: skip samples */
original_rate = read_s32le(data_offset+0x0c,sf);
/* 0x10: gain */
/* 0x12: mapping family */
/* parse 2nd page: opus tags (also mandatory) */
if (!get_ogg_page_size(sf, start_offset+page_size, &data_offset, &page_size))
goto fail;
if (!is_id32be(data_offset+0x00,sf, "Opus") ||
!is_id32be(data_offset+0x04,sf, "Tags"))
goto fail;
loop_flag = 0;
{
char user_comment[1024+1];
off_t offset;
int vendor_size, comment_count, user_comment_size, user_comment_max;
int i;
int has_encoder_options = 0, has_title = 0;
vendor_size = read_s32le(data_offset+0x08,sf);
comment_count = read_s32le(data_offset+0x0c+vendor_size,sf);
/* parse comments */
offset = data_offset + 0x0c + vendor_size + 0x04;
for (i = 0; i < comment_count; i++) {
user_comment_size = read_s32le(offset+0x00,sf);
user_comment_max = user_comment_size > 1024 ? 1024 : user_comment_size;
read_string(user_comment,user_comment_max+1, offset+0x04,sf);
/* parse loop strings */
if (strstr(user_comment,"LOOP_START=")==user_comment) { /* Monster Boy and the Cursed Kingdom (Switch) */
loop_start = atol(strrchr(user_comment,'=')+1);
loop_flag = (loop_start >= 0);
}
else if (strstr(user_comment,"LOOP_END=")==user_comment) { /* LOOP_START pair */
loop_end = atol(strrchr(user_comment,'=')+1);
}
else if (strstr(user_comment,"ENCODER_OPTIONS=")==user_comment) { /* for detection */
has_encoder_options = 1;
}
else if (strstr(user_comment,"TITLE=")==user_comment) { /* for detection */
has_title = 1;
}
else if (strstr(user_comment,"LoopStart=")==user_comment) { /* Utawarerumono: Mask of Truth (PC) */
loop_start= atol(strrchr(user_comment,'=')+1);
loop_flag = (loop_start >= 0);
}
else if (strstr(user_comment,"LoopEnd=")==user_comment) { /* LoopStart pair */
loop_end = atol(strrchr(user_comment,'=')+1);
}
else if (strstr(user_comment, "loops=") == user_comment) { /* The Legend of Heroes: Trails of Cold Steel III (Switch) */
sscanf(strrchr(user_comment, '=') + 1, "%d-%d", &loop_start, &loop_end);
loop_flag = 1;
}
//;VGM_LOG("OggOpus: user_comment=%s\n", user_comment);
offset += 0x04 + user_comment_size;
}
/* Monster Boy has loop points for 44100hz (what), but Opus is resampled so
* they must be adjusted (with extra checks just in case). */
if (loop_flag && original_rate < 48000 && has_encoder_options && has_title) {
float modifier = 48000.0f / (float)original_rate;
loop_start = loop_start * modifier;
loop_end = loop_end * modifier;
}
}
/* build the VGMSTREAM */
vgmstream = allocate_vgmstream(channel_count, loop_flag);
if (!vgmstream) goto fail;
vgmstream->meta_type = meta_OGG_OPUS;
vgmstream->sample_rate = 48000; /* Opus always resamples to this */
vgmstream->num_samples = ogg_get_num_samples(sf, 0x00);
vgmstream->loop_start_sample = loop_start;
vgmstream->loop_end_sample = loop_end;
#ifdef VGM_USE_FFMPEG
{
vgmstream->codec_data = init_ffmpeg_offset(sf, start_offset, get_streamfile_size(sf));
if (!vgmstream->codec_data) goto fail;
vgmstream->coding_type = coding_FFmpeg;
vgmstream->layout_type = layout_none;
vgmstream->channel_layout = ffmpeg_get_channel_layout(vgmstream->codec_data);
/* FFmpeg+libopus handles skip samples ok, FFmpeg+opus doesn't */
}
#else
goto fail;
#endif
if (!vgmstream_open_stream(vgmstream,sf,start_offset))
goto fail;
return vgmstream;
fail:
close_vgmstream(vgmstream);
return NULL;
}
/* parse OggS's bizarre segment table */
static int get_ogg_page_size(STREAMFILE* sf, off_t page_offset, off_t* p_data_offset, size_t* p_page_size) {
uint8_t segments;
size_t page_size = 0;
int i;
if (!is_id32be(page_offset+0x00,sf, "OggS"))
goto fail;
/* read all segment sizes */
segments = read_u8(page_offset+0x1a, sf);
for (i = 0; i < segments; i++) {
page_size += read_u8(page_offset + 0x1b + i, sf);
}
page_size += 0x1b + segments;
if (p_data_offset) *p_data_offset = page_offset + 0x1b + segments;
if (p_page_size) *p_page_size = page_size;
return 1;
fail:
return 0;
}
/* Ogg doesn't have num_samples info, must manually seek+read last granule
* (Xiph is insistent this is the One True Way). */
static int ogg_get_num_samples(STREAMFILE *sf, off_t start_offset) {
uint32_t expected_id = get_id32be("OggS");
off_t offset = get_streamfile_size(sf) - 0x04-0x01-0x01-0x08-0x04-0x04-0x04;
//todo better buffer reads (Ogg page max is 0xFFFF)
//lame way to force buffer, assuming it's around that
read_u32be(offset - 0x4000, sf);
while (offset >= start_offset) {
uint32_t current_id = read_u32be(offset, sf);
if (current_id == expected_id) { /* if more checks are needed last page starts with 0x0004 */
return read_s32le(offset+0x04+0x01+0x01, sf); /* get last granule = total samples (64b but whatevs) */
}
offset--;
}
return 0;
}