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ffmpeg.wasm-core
Commit ecaa6cf7 authored by Hendrik Leppkes's avatar Hendrik Leppkes
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Merge commit '971177f7' 

* commit '971177f7':
  dcadec: scan for extensions in a separate function
Merged-by: 's avatarHendrik Leppkes <h.leppkes@gmail.com>
parents 15796932 971177f7
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Showing with 109 additions and 99 deletions
libavcodec/dcadec.c
View file @ ecaa6cf7
......@@ -1453,6 +1453,114 @@ static float dca_dmix_code(unsigned code)
return ((ff_dca_dmixtable[code] ^ sign) - sign) * (1.0 / (1 << 15));
}
static int scan_for_extensions(AVCodecContext *avctx)
{
DCAContext *s = avctx->priv_data;
int core_ss_end, ret;
core_ss_end = FFMIN(s->frame_size, s->dca_buffer_size) * 8;
/* only scan for extensions if ext_descr was unknown or indicated a
* supported XCh extension */
if (s->core_ext_mask < 0 || s->core_ext_mask & (DCA_EXT_XCH | DCA_EXT_XXCH)) {
/* if ext_descr was unknown, clear s->core_ext_mask so that the
* extensions scan can fill it up */
s->core_ext_mask = FFMAX(s->core_ext_mask, 0);
/* extensions start at 32-bit boundaries into bitstream */
skip_bits_long(&s->gb, (-get_bits_count(&s->gb)) & 31);
while (core_ss_end - get_bits_count(&s->gb) >= 32) {
uint32_t bits = get_bits_long(&s->gb, 32);
int i;
switch (bits) {
case DCA_SYNCWORD_XCH: {
int ext_amode, xch_fsize;
s->xch_base_channel = s->prim_channels;
/* validate sync word using XCHFSIZE field */
xch_fsize = show_bits(&s->gb, 10);
if ((s->frame_size != (get_bits_count(&s->gb) >> 3) - 4 + xch_fsize) &&
(s->frame_size != (get_bits_count(&s->gb) >> 3) - 4 + xch_fsize + 1))
continue;
/* skip length-to-end-of-frame field for the moment */
skip_bits(&s->gb, 10);
s->core_ext_mask |= DCA_EXT_XCH;
/* extension amode(number of channels in extension) should be 1 */
/* AFAIK XCh is not used for more channels */
if ((ext_amode = get_bits(&s->gb, 4)) != 1) {
av_log(avctx, AV_LOG_ERROR,
"XCh extension amode %d not supported!\n",
ext_amode);
continue;
}
if (s->xch_base_channel < 2) {
avpriv_request_sample(avctx, "XCh with fewer than 2 base channels");
continue;
}
/* much like core primary audio coding header */
dca_parse_audio_coding_header(s, s->xch_base_channel, 0);
for (i = 0; i < (s->sample_blocks / 8); i++)
if ((ret = dca_decode_block(s, s->xch_base_channel, i))) {
av_log(avctx, AV_LOG_ERROR, "error decoding XCh extension\n");
continue;
}
s->xch_present = 1;
break;
}
case DCA_SYNCWORD_XXCH:
/* XXCh: extended channels */
/* usually found either in core or HD part in DTS-HD HRA streams,
* but not in DTS-ES which contains XCh extensions instead */
s->core_ext_mask |= DCA_EXT_XXCH;
ff_dca_xxch_decode_frame(s);
break;
case 0x1d95f262: {
int fsize96 = show_bits(&s->gb, 12) + 1;
if (s->frame_size != (get_bits_count(&s->gb) >> 3) - 4 + fsize96)
continue;
av_log(avctx, AV_LOG_DEBUG, "X96 extension found at %d bits\n",
get_bits_count(&s->gb));
skip_bits(&s->gb, 12);
av_log(avctx, AV_LOG_DEBUG, "FSIZE96 = %d bytes\n", fsize96);
av_log(avctx, AV_LOG_DEBUG, "REVNO = %d\n", get_bits(&s->gb, 4));
s->core_ext_mask |= DCA_EXT_X96;
break;
}
}
skip_bits_long(&s->gb, (-get_bits_count(&s->gb)) & 31);
}
} else {
/* no supported extensions, skip the rest of the core substream */
skip_bits_long(&s->gb, core_ss_end - get_bits_count(&s->gb));
}
if (s->core_ext_mask & DCA_EXT_X96)
s->profile = FF_PROFILE_DTS_96_24;
else if (s->core_ext_mask & (DCA_EXT_XCH | DCA_EXT_XXCH))
s->profile = FF_PROFILE_DTS_ES;
/* check for ExSS (HD part) */
if (s->dca_buffer_size - s->frame_size > 32 &&
get_bits_long(&s->gb, 32) == DCA_SYNCWORD_SUBSTREAM)
ff_dca_exss_parse_header(s);
return ret;
}
/**
* Main frame decoding function
* FIXME add arguments
......@@ -1472,7 +1580,6 @@ static int dca_decode_frame(AVCodecContext *avctx, void *data,
float *src_chan;
float *dst_chan;
DCAContext *s = avctx->priv_data;
int core_ss_end;
int channels, full_channels;
float scale;
int achan;
......@@ -1564,104 +1671,7 @@ static int dca_decode_frame(AVCodecContext *avctx, void *data,
else
s->core_ext_mask = 0;
core_ss_end = FFMIN(s->frame_size, s->dca_buffer_size) * 8;
/* only scan for extensions if ext_descr was unknown or indicated a
* supported XCh extension */
if (s->core_ext_mask < 0 || s->core_ext_mask & (DCA_EXT_XCH | DCA_EXT_XXCH)) {
/* if ext_descr was unknown, clear s->core_ext_mask so that the
* extensions scan can fill it up */
s->core_ext_mask = FFMAX(s->core_ext_mask, 0);
/* extensions start at 32-bit boundaries into bitstream */
skip_bits_long(&s->gb, (-get_bits_count(&s->gb)) & 31);
while (core_ss_end - get_bits_count(&s->gb) >= 32) {
uint32_t bits = get_bits_long(&s->gb, 32);
switch (bits) {
case DCA_SYNCWORD_XCH: {
int ext_amode, xch_fsize;
s->xch_base_channel = s->prim_channels;
/* validate sync word using XCHFSIZE field */
xch_fsize = show_bits(&s->gb, 10);
if ((s->frame_size != (get_bits_count(&s->gb) >> 3) - 4 + xch_fsize) &&
(s->frame_size != (get_bits_count(&s->gb) >> 3) - 4 + xch_fsize + 1))
continue;
/* skip length-to-end-of-frame field for the moment */
skip_bits(&s->gb, 10);
s->core_ext_mask |= DCA_EXT_XCH;
/* extension amode(number of channels in extension) should be 1 */
/* AFAIK XCh is not used for more channels */
if ((ext_amode = get_bits(&s->gb, 4)) != 1) {
av_log(avctx, AV_LOG_ERROR,
"XCh extension amode %d not supported!\n",
ext_amode);
continue;
}
if (s->xch_base_channel < 2) {
avpriv_request_sample(avctx, "XCh with fewer than 2 base channels");
continue;
}
/* much like core primary audio coding header */
dca_parse_audio_coding_header(s, s->xch_base_channel, 0);
for (i = 0; i < (s->sample_blocks / 8); i++)
if ((ret = dca_decode_block(s, s->xch_base_channel, i))) {
av_log(avctx, AV_LOG_ERROR, "error decoding XCh extension\n");
continue;
}
s->xch_present = 1;
break;
}
case DCA_SYNCWORD_XXCH:
/* XXCh: extended channels */
/* usually found either in core or HD part in DTS-HD HRA streams,
* but not in DTS-ES which contains XCh extensions instead */
s->core_ext_mask |= DCA_EXT_XXCH;
ff_dca_xxch_decode_frame(s);
break;
case 0x1d95f262: {
int fsize96 = show_bits(&s->gb, 12) + 1;
if (s->frame_size != (get_bits_count(&s->gb) >> 3) - 4 + fsize96)
continue;
av_log(avctx, AV_LOG_DEBUG, "X96 extension found at %d bits\n",
get_bits_count(&s->gb));
skip_bits(&s->gb, 12);
av_log(avctx, AV_LOG_DEBUG, "FSIZE96 = %d bytes\n", fsize96);
av_log(avctx, AV_LOG_DEBUG, "REVNO = %d\n", get_bits(&s->gb, 4));
s->core_ext_mask |= DCA_EXT_X96;
break;
}
}
skip_bits_long(&s->gb, (-get_bits_count(&s->gb)) & 31);
}
} else {
/* no supported extensions, skip the rest of the core substream */
skip_bits_long(&s->gb, core_ss_end - get_bits_count(&s->gb));
}
if (s->core_ext_mask & DCA_EXT_X96)
s->profile = FF_PROFILE_DTS_96_24;
else if (s->core_ext_mask & (DCA_EXT_XCH | DCA_EXT_XXCH))
s->profile = FF_PROFILE_DTS_ES;
/* check for ExSS (HD part) */
if (s->dca_buffer_size - s->frame_size > 32 &&
get_bits_long(&s->gb, 32) == DCA_SYNCWORD_SUBSTREAM)
ff_dca_exss_parse_header(s);
ret = scan_for_extensions(avctx);
avctx->profile = s->profile;
......
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