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Code Issues Releases Activity

adpcm: convert adpcm_ima_qt to bytestream2.

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This commit is contained in:
Ronald S. Bultje 2012-03-17 12:45:09 -07:00
parent c346f6304c
commit 9604307dd8
1 changed files with 14 additions and 13 deletions
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27
libavcodec/adpcm.c
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@ -544,6 +544,7 @@ static int adpcm_decode_frame(AVCodecContext *avctx, void *data,
int st; /* stereo */
int count1, count2;
int nb_samples, coded_samples, ret;
GetByteContext gb;
nb_samples = get_nb_samples(avctx, buf, buf_size, &coded_samples);
if (nb_samples <= 0) {
@ -568,6 +569,7 @@ static int adpcm_decode_frame(AVCodecContext *avctx, void *data,
}
src = buf;
bytestream2_init(&gb, buf, buf_size);
st = avctx->channels == 2 ? 1 : 0;
@ -576,20 +578,18 @@ static int adpcm_decode_frame(AVCodecContext *avctx, void *data,
/* In QuickTime, IMA is encoded by chunks of 34 bytes (=64 samples).
Channel data is interleaved per-chunk. */
for (channel = 0; channel < avctx->channels; channel++) {
int16_t predictor;
int predictor;
int step_index;
cs = &(c->status[channel]);
/* (pppppp) (piiiiiii) */
/* Bits 15-7 are the _top_ 9 bits of the 16-bit initial predictor value */
predictor = AV_RB16(src);
predictor = sign_extend(bytestream2_get_be16u(&gb), 16);
step_index = predictor & 0x7F;
predictor &= 0xFF80;
src += 2;
predictor &= ~0x7F;
if (cs->step_index == step_index) {
int diff = (int)predictor - cs->predictor;
int diff = predictor - cs->predictor;
if (diff < 0)
diff = - diff;
if (diff > 0x7f)
@ -600,19 +600,20 @@ static int adpcm_decode_frame(AVCodecContext *avctx, void *data,
cs->predictor = predictor;
}
if (cs->step_index > 88){
av_log(avctx, AV_LOG_ERROR, "ERROR: step_index = %i\n", cs->step_index);
cs->step_index = 88;
if (cs->step_index > 88u){
av_log(avctx, AV_LOG_ERROR, "ERROR: step_index[%d] = %i\n",
channel, cs->step_index);
return AVERROR_INVALIDDATA;
}
samples = (short *)c->frame.data[0] + channel;
for (m = 0; m < 32; m++) {
*samples = adpcm_ima_qt_expand_nibble(cs, src[0] & 0x0F, 3);
int byte = bytestream2_get_byteu(&gb);
*samples = adpcm_ima_qt_expand_nibble(cs, byte & 0x0F, 3);
samples += avctx->channels;
*samples = adpcm_ima_qt_expand_nibble(cs, src[0] >> 4 , 3);
*samples = adpcm_ima_qt_expand_nibble(cs, byte >> 4 , 3);
samples += avctx->channels;
src ++;
}
}
break;
@ -1239,7 +1240,7 @@ static int adpcm_decode_frame(AVCodecContext *avctx, void *data,
*got_frame_ptr = 1;
*(AVFrame *)data = c->frame;
return src - buf;
return src == buf ? bytestream2_tell(&gb) : src - buf;
}