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THP PCM decoder, used on the Nintendo GameCube.

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patch by Marco Gerards, mgerards xs4all nl

Originally committed as revision 8646 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Marco Gerards
2007-04-07 16:03:23 +00:00
committed by Diego Biurrun
parent efd2afc2ae
commit d1e0d21f94
6 changed files with 111 additions and 4 deletions
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68
libavcodec/adpcm.c
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@@ -29,6 +29,7 @@
* by Mike Melanson (melanson@pcisys.net)
* CD-ROM XA ADPCM codec by BERO
* EA ADPCM decoder by Robin Kay (komadori@myrealbox.com)
* THP ADPCM decoder by Marco Gerards (mgerards@xs4all.nl)
*
* Features and limitations:
*
@@ -1308,6 +1309,72 @@ static int adpcm_decode_frame(AVCodecContext *avctx,
src++;
}
break;
case CODEC_ID_ADPCM_THP:
{
GetBitContext gb;
int table[16][2];
unsigned int samplecnt;
int prev1[2], prev2[2];
int ch;
if (buf_size < 80) {
av_log(avctx, AV_LOG_ERROR, "frame too small\n");
return -1;
}
init_get_bits(&gb, src, buf_size * 8);
src += buf_size;
get_bits_long(&gb, 32); /* Channel size */
samplecnt = get_bits_long(&gb, 32);
for (ch = 0; ch < 2; ch++)
for (i = 0; i < 16; i++)
table[i][ch] = get_sbits(&gb, 16);
/* Initialize the previous sample. */
for (ch = 0; ch < 2; ch++) {
prev1[ch] = get_sbits(&gb, 16);
prev2[ch] = get_sbits(&gb, 16);
}
if (samplecnt >= (samples_end - samples) / (st + 1)) {
av_log(avctx, AV_LOG_ERROR, "allocated output buffer is too small\n");
return -1;
}
for (ch = 0; ch <= st; ch++) {
samples = (unsigned short *) data + ch;
/* Read in every sample for this channel. */
for (i = 0; i < samplecnt / 14; i++) {
uint8_t index = get_bits (&gb, 4) & 7;
unsigned int exp = get_bits (&gb, 4);
int factor1 = table[index * 2][ch];
int factor2 = table[index * 2 + 1][ch];
/* Decode 14 samples. */
for (n = 0; n < 14; n++) {
int sampledat = get_sbits (&gb, 4);
*samples = ((prev1[ch]*factor1
+ prev2[ch]*factor2) >> 11) + (sampledat << exp);
prev2[ch] = prev1[ch];
prev1[ch] = *samples++;
/* In case of stereo, skip one sample, this sample
is for the other channel. */
samples += st;
}
}
}
/* In the previous loop, in case stereo is used, samples is
increased exactly one time too often. */
samples -= st;
break;
}
default:
return -1;
}
@@ -1368,5 +1435,6 @@ ADPCM_CODEC(CODEC_ID_ADPCM_YAMAHA, adpcm_yamaha);
ADPCM_CODEC(CODEC_ID_ADPCM_SBPRO_4, adpcm_sbpro_4);
ADPCM_CODEC(CODEC_ID_ADPCM_SBPRO_3, adpcm_sbpro_3);
ADPCM_CODEC(CODEC_ID_ADPCM_SBPRO_2, adpcm_sbpro_2);
ADPCM_CODEC(CODEC_ID_ADPCM_THP, adpcm_thp);
#undef ADPCM_CODEC