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ac3enc: clean up count_frame_bits() and count_frame_bits_fixed()

This commit is contained in:
Justin Ruggles 2011-04-30 15:52:55 -04:00
parent c4fb3b0327
commit 257de756fb
1 changed files with 48 additions and 22 deletions
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70
libavcodec/ac3enc.c
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@ -818,35 +818,57 @@ static void count_frame_bits_fixed(AC3EncodeContext *s)
* no auxilliary data * no auxilliary data
*/ */
/* header size */ /* header */
frame_bits = 65; frame_bits = 65;
frame_bits += frame_bits_inc[s->channel_mode]; frame_bits += frame_bits_inc[s->channel_mode];
/* audio blocks */ /* audio blocks */
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) { for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
frame_bits += s->fbw_channels * 2 + 2; /* blksw * c, dithflag * c, dynrnge, cplstre */ /* block switch flags */
if (s->channel_mode == AC3_CHMODE_STEREO) { frame_bits += s->fbw_channels;
frame_bits++; /* rematstr */
}
frame_bits += 2 * s->fbw_channels; /* chexpstr[2] * c */
if (s->lfe_on)
frame_bits++; /* lfeexpstr */
frame_bits++; /* baie */
frame_bits++; /* snr */
frame_bits += 2; /* delta / skip */
}
frame_bits++; /* cplinu for block 0 */
/* bit alloc info */
/* sdcycod[2], fdcycod[2], sgaincod[2], dbpbcod[2], floorcod[3] */
/* csnroffset[6] */
/* (fsnoffset[4] + fgaincod[4]) * c */
frame_bits += 2*4 + 3 + 6 + s->channels * (4 + 3);
/* auxdatae, crcrsv */ /* dither flags */
frame_bits += 2; frame_bits += s->fbw_channels;
/* dynamic range */
frame_bits++;
/* coupling strategy */
frame_bits++;
if (!blk)
frame_bits++;
/* stereo rematrixing */
if (s->channel_mode == AC3_CHMODE_STEREO)
frame_bits++;
/* exponent strategy */
frame_bits += 2 * s->fbw_channels;
if (s->lfe_on)
frame_bits++;
/* bit allocation params */
frame_bits++;
if (!blk)
frame_bits += 2 + 2 + 2 + 2 + 3;
/* snr offsets and fast gain codes */
frame_bits++;
if (!blk)
frame_bits += 6 + s->channels * (4 + 3);
/* delta bit allocation */
frame_bits++;
/* skipped data */
frame_bits++;
}
/* auxiliary data */
frame_bits++;
/* CRC */ /* CRC */
frame_bits += 16; frame_bits += 1 + 16;
s->frame_bits_fixed = frame_bits; s->frame_bits_fixed = frame_bits;
} }
@ -896,6 +918,7 @@ static void count_frame_bits(AC3EncodeContext *s)
int blk, ch; int blk, ch;
int frame_bits = 0; int frame_bits = 0;
/* header */
if (opt->audio_production_info) if (opt->audio_production_info)
frame_bits += 7; frame_bits += 7;
if (s->bitstream_id == 6) { if (s->bitstream_id == 6) {
@ -905,6 +928,7 @@ static void count_frame_bits(AC3EncodeContext *s)
frame_bits += 14; frame_bits += 14;
} }
/* audio blocks */
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) { for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
/* stereo rematrixing */ /* stereo rematrixing */
if (s->channel_mode == AC3_CHMODE_STEREO && if (s->channel_mode == AC3_CHMODE_STEREO &&
@ -912,11 +936,13 @@ static void count_frame_bits(AC3EncodeContext *s)
frame_bits += s->num_rematrixing_bands; frame_bits += s->num_rematrixing_bands;
} }
/* bandwidth codes & gain range */
for (ch = 0; ch < s->fbw_channels; ch++) { for (ch = 0; ch < s->fbw_channels; ch++) {
if (s->exp_strategy[ch][blk] != EXP_REUSE) if (s->exp_strategy[ch][blk] != EXP_REUSE)
frame_bits += 6 + 2; /* chbwcod[6], gainrng[2] */ frame_bits += 6 + 2;
} }
} }
s->frame_bits = s->frame_bits_fixed + frame_bits; s->frame_bits = s->frame_bits_fixed + frame_bits;
} }