Signed-off-by: Luca Barbato <[email protected]>
---
libavcodec/ac3_parser.c | 45 ++++++++++++++++---------------
libavcodec/ac3dec.c | 70 ++++++++++++++++++++++++++-----------------------
2 files changed, 61 insertions(+), 54 deletions(-)
diff --git a/libavcodec/ac3_parser.c b/libavcodec/ac3_parser.c
index a7db17e..66dc27f 100644
--- a/libavcodec/ac3_parser.c
+++ b/libavcodec/ac3_parser.c
@@ -48,18 +48,19 @@ static const uint8_t center_levels[4] = { 4, 5, 6, 5 };
static const uint8_t surround_levels[4] = { 4, 6, 7, 6 };
-int avpriv_ac3_parse_header(BitstreamContext *bc, AC3HeaderInfo *hdr)
+int avpriv_ac3_parse_header(BitstreamContext *bcp, AC3HeaderInfo *hdr)
{
+ BitstreamContext bc = *bcp;
int frame_size_code;
memset(hdr, 0, sizeof(*hdr));
- hdr->sync_word = bitstream_read(bc, 16);
+ hdr->sync_word = bitstream_read(&bc, 16);
if(hdr->sync_word != 0x0B77)
return AAC_AC3_PARSE_ERROR_SYNC;
/* read ahead to bsid to distinguish between AC-3 and E-AC-3 */
- hdr->bitstream_id = bitstream_peek(bc, 29) & 0x1F;
+ hdr->bitstream_id = bitstream_peek(&bc, 29) & 0x1F;
if(hdr->bitstream_id > 16)
return AAC_AC3_PARSE_ERROR_BSID;
@@ -74,29 +75,29 @@ int avpriv_ac3_parse_header(BitstreamContext *bc,
AC3HeaderInfo *hdr)
if(hdr->bitstream_id <= 10) {
/* Normal AC-3 */
- hdr->crc1 = bitstream_read(bc, 16);
- hdr->sr_code = bitstream_read(bc, 2);
+ hdr->crc1 = bitstream_read(&bc, 16);
+ hdr->sr_code = bitstream_read(&bc, 2);
if(hdr->sr_code == 3)
return AAC_AC3_PARSE_ERROR_SAMPLE_RATE;
- frame_size_code = bitstream_read(bc, 6);
+ frame_size_code = bitstream_read(&bc, 6);
if(frame_size_code > 37)
return AAC_AC3_PARSE_ERROR_FRAME_SIZE;
- bitstream_skip(bc, 5); // skip bsid, already got it
+ bitstream_skip(&bc, 5); // skip bsid, already got it
- hdr->bitstream_mode = bitstream_read(bc, 3);
- hdr->channel_mode = bitstream_read(bc, 3);
+ hdr->bitstream_mode = bitstream_read(&bc, 3);
+ hdr->channel_mode = bitstream_read(&bc, 3);
if(hdr->channel_mode == AC3_CHMODE_STEREO) {
- hdr->dolby_surround_mode = bitstream_read(bc, 2);
+ hdr->dolby_surround_mode = bitstream_read(&bc, 2);
} else {
if((hdr->channel_mode & 1) && hdr->channel_mode != AC3_CHMODE_MONO)
- hdr->center_mix_level = center_levels[bitstream_read(bc, 2)];
+ hdr->center_mix_level = center_levels[bitstream_read(&bc,
2)];
if(hdr->channel_mode & 4)
- hdr->surround_mix_level = surround_levels[bitstream_read(bc,
2)];
+ hdr->surround_mix_level = surround_levels[bitstream_read(&bc,
2)];
}
- hdr->lfe_on = bitstream_read_bit(bc);
+ hdr->lfe_on = bitstream_read_bit(&bc);
hdr->sr_shift = FFMAX(hdr->bitstream_id, 8) - 8;
hdr->sample_rate = ff_ac3_sample_rate_tab[hdr->sr_code] >>
hdr->sr_shift;
@@ -108,31 +109,31 @@ int avpriv_ac3_parse_header(BitstreamContext *bc,
AC3HeaderInfo *hdr)
} else {
/* Enhanced AC-3 */
hdr->crc1 = 0;
- hdr->frame_type = bitstream_read(bc, 2);
+ hdr->frame_type = bitstream_read(&bc, 2);
if(hdr->frame_type == EAC3_FRAME_TYPE_RESERVED)
return AAC_AC3_PARSE_ERROR_FRAME_TYPE;
- hdr->substreamid = bitstream_read(bc, 3);
+ hdr->substreamid = bitstream_read(&bc, 3);
- hdr->frame_size = (bitstream_read(bc, 11) + 1) << 1;
+ hdr->frame_size = (bitstream_read(&bc, 11) + 1) << 1;
if(hdr->frame_size < AC3_HEADER_SIZE)
return AAC_AC3_PARSE_ERROR_FRAME_SIZE;
- hdr->sr_code = bitstream_read(bc, 2);
+ hdr->sr_code = bitstream_read(&bc, 2);
if (hdr->sr_code == 3) {
- int sr_code2 = bitstream_read(bc, 2);
+ int sr_code2 = bitstream_read(&bc, 2);
if(sr_code2 == 3)
return AAC_AC3_PARSE_ERROR_SAMPLE_RATE;
hdr->sample_rate = ff_ac3_sample_rate_tab[sr_code2] / 2;
hdr->sr_shift = 1;
} else {
- hdr->num_blocks = eac3_blocks[bitstream_read(bc, 2)];
+ hdr->num_blocks = eac3_blocks[bitstream_read(&bc, 2)];
hdr->sample_rate = ff_ac3_sample_rate_tab[hdr->sr_code];
hdr->sr_shift = 0;
}
- hdr->channel_mode = bitstream_read(bc, 3);
- hdr->lfe_on = bitstream_read_bit(bc);
+ hdr->channel_mode = bitstream_read(&bc, 3);
+ hdr->lfe_on = bitstream_read_bit(&bc);
hdr->bit_rate = (uint32_t)(8.0 * hdr->frame_size * hdr->sample_rate /
(hdr->num_blocks * 256.0));
@@ -142,6 +143,8 @@ int avpriv_ac3_parse_header(BitstreamContext *bc,
AC3HeaderInfo *hdr)
if (hdr->lfe_on)
hdr->channel_layout |= AV_CH_LOW_FREQUENCY;
+ *bcp = bc;
+
return 0;
}
diff --git a/libavcodec/ac3dec.c b/libavcodec/ac3dec.c
index b1a3c8d..62e9868 100644
--- a/libavcodec/ac3dec.c
+++ b/libavcodec/ac3dec.c
@@ -213,52 +213,54 @@ static av_cold int ac3_decode_init(AVCodecContext *avctx)
*/
static int ac3_parse_header(AC3DecodeContext *s)
{
- BitstreamContext *bc = &s->bc;
+ BitstreamContext bc = s->bc;
int i;
/* read the rest of the bsi. read twice for dual mono mode. */
i = !s->channel_mode;
do {
- bitstream_skip(bc, 5); // skip dialog normalization
- if (bitstream_read_bit(bc))
- bitstream_skip(bc, 8); // skip compression
- if (bitstream_read_bit(bc))
- bitstream_skip(bc, 8); // skip language code
- if (bitstream_read_bit(bc))
- bitstream_skip(bc, 7); // skip audio production information
+ bitstream_skip(&bc, 5); // skip dialog normalization
+ if (bitstream_read_bit(&bc))
+ bitstream_skip(&bc, 8); // skip compression
+ if (bitstream_read_bit(&bc))
+ bitstream_skip(&bc, 8); // skip language code
+ if (bitstream_read_bit(&bc))
+ bitstream_skip(&bc, 7); // skip audio production information
} while (i--);
- bitstream_skip(bc, 2); // skip copyright bit and original bitstream bit
+ bitstream_skip(&bc, 2); // skip copyright bit and original bitstream bit
/* skip the timecodes or parse the Alternate Bit Stream Syntax */
if (s->bitstream_id != 6) {
- if (bitstream_read_bit(bc))
- bitstream_skip(bc, 14); // skip timecode1
- if (bitstream_read_bit(bc))
- bitstream_skip(bc, 14); // skip timecode2
+ if (bitstream_read_bit(&bc))
+ bitstream_skip(&bc, 14); // skip timecode1
+ if (bitstream_read_bit(&bc))
+ bitstream_skip(&bc, 14); // skip timecode2
} else {
- if (bitstream_read_bit(bc)) {
- s->preferred_downmix = bitstream_read(bc, 2);
- s->center_mix_level_ltrt = bitstream_read(bc, 3);
- s->surround_mix_level_ltrt = av_clip(bitstream_read(bc, 3), 3, 7);
- s->center_mix_level = bitstream_read(bc, 3);
- s->surround_mix_level = av_clip(bitstream_read(bc, 3), 3, 7);
+ if (bitstream_read_bit(&bc)) {
+ s->preferred_downmix = bitstream_read(&bc, 2);
+ s->center_mix_level_ltrt = bitstream_read(&bc, 3);
+ s->surround_mix_level_ltrt = av_clip(bitstream_read(&bc, 3), 3, 7);
+ s->center_mix_level = bitstream_read(&bc, 3);
+ s->surround_mix_level = av_clip(bitstream_read(&bc, 3), 3, 7);
}
- if (bitstream_read_bit(bc)) {
- s->dolby_surround_ex_mode = bitstream_read(bc, 2);
- s->dolby_headphone_mode = bitstream_read(bc, 2);
- bitstream_skip(bc, 10); // skip adconvtyp (1), xbsi2 (8), encinfo
(1)
+ if (bitstream_read_bit(&bc)) {
+ s->dolby_surround_ex_mode = bitstream_read(&bc, 2);
+ s->dolby_headphone_mode = bitstream_read(&bc, 2);
+ bitstream_skip(&bc, 10); // skip adconvtyp (1), xbsi2 (8), encinfo
(1)
}
}
/* skip additional bitstream info */
- if (bitstream_read_bit(bc)) {
- i = bitstream_read(bc, 6);
+ if (bitstream_read_bit(&bc)) {
+ i = bitstream_read(&bc, 6);
do {
- bitstream_skip(bc, 8);
+ bitstream_skip(&bc, 8);
} while (i--);
}
+ s->bc = bc;
+
return 0;
}
@@ -465,7 +467,7 @@ static void ac3_decode_transform_coeffs_ch(AC3DecodeContext
*s, int ch_index, ma
int8_t *exps = s->dexps[ch_index];
int32_t *coeffs = s->fixed_coeffs[ch_index];
int dither = (ch_index == CPL_CH) || s->dither_flag[ch_index];
- BitstreamContext *bc = &s->bc;
+ BitstreamContext bc = s->bc;
int freq;
for (freq = start_freq; freq < end_freq; freq++) {
@@ -484,7 +486,7 @@ static void ac3_decode_transform_coeffs_ch(AC3DecodeContext
*s, int ch_index, ma
m->b1--;
mantissa = m->b1_mant[m->b1];
} else {
- int bits = bitstream_read(bc, 5);
+ int bits = bitstream_read(&bc, 5);
mantissa = b1_mantissas[bits][0];
m->b1_mant[1] = b1_mantissas[bits][1];
m->b1_mant[0] = b1_mantissas[bits][2];
@@ -496,7 +498,7 @@ static void ac3_decode_transform_coeffs_ch(AC3DecodeContext
*s, int ch_index, ma
m->b2--;
mantissa = m->b2_mant[m->b2];
} else {
- int bits = bitstream_read(bc, 7);
+ int bits = bitstream_read(&bc, 7);
mantissa = b2_mantissas[bits][0];
m->b2_mant[1] = b2_mantissas[bits][1];
m->b2_mant[0] = b2_mantissas[bits][2];
@@ -504,30 +506,32 @@ static void
ac3_decode_transform_coeffs_ch(AC3DecodeContext *s, int ch_index, ma
}
break;
case 3:
- mantissa = b3_mantissas[bitstream_read(bc, 3)];
+ mantissa = b3_mantissas[bitstream_read(&bc, 3)];
break;
case 4:
if (m->b4) {
m->b4 = 0;
mantissa = m->b4_mant;
} else {
- int bits = bitstream_read(bc, 7);
+ int bits = bitstream_read(&bc, 7);
mantissa = b4_mantissas[bits][0];
m->b4_mant = b4_mantissas[bits][1];
m->b4 = 1;
}
break;
case 5:
- mantissa = b5_mantissas[bitstream_read(bc, 4)];
+ mantissa = b5_mantissas[bitstream_read(&bc, 4)];
break;
default: /* 6 to 15 */
/* Shift mantissa and sign-extend it. */
- mantissa = bitstream_read_signed(bc, quantization_tab[bap]);
+ mantissa = bitstream_read_signed(&bc, quantization_tab[bap]);
mantissa <<= 24 - quantization_tab[bap];
break;
}
coeffs[freq] = mantissa >> exps[freq];
}
+
+ s->bc = bc;
}
/**
--
2.6.1
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