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Code Issues Releases Activity

adpcm: convert adpcm_dk3 to bytestream2.

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This commit is contained in:
Ronald S. Bultje 2012-03-17 13:39:54 -07:00
parent d570a96808
commit 1da9587026
1 changed files with 25 additions and 32 deletions
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57
libavcodec/adpcm.c
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@ -514,24 +514,6 @@ static int get_nb_samples(AVCodecContext *avctx, const uint8_t *buf,
return nb_samples;
}
/* DK3 ADPCM support macro */
#define DK3_GET_NEXT_NIBBLE() \
if (decode_top_nibble_next) \
{ \
nibble = last_byte >> 4; \
decode_top_nibble_next = 0; \
} \
else \
{ \
if (end_of_packet) \
break; \
last_byte = *src++; \
if (src >= buf + buf_size) \
end_of_packet = 1; \
nibble = last_byte & 0x0F; \
decode_top_nibble_next = 1; \
}
static int adpcm_decode_frame(AVCodecContext *avctx, void *data,
int *got_frame_ptr, AVPacket *avpkt)
{
@ -733,26 +715,37 @@ static int adpcm_decode_frame(AVCodecContext *avctx, void *data,
break;
case CODEC_ID_ADPCM_IMA_DK3:
{
unsigned char last_byte = 0;
unsigned char nibble;
int last_byte = 0;
int nibble;
int decode_top_nibble_next = 0;
int end_of_packet = 0;
int diff_channel;
const int16_t *samples_end = samples + avctx->channels * nb_samples;
if (avctx->block_align != 0 && buf_size > avctx->block_align)
buf_size = avctx->block_align;
c->status[0].predictor = (int16_t)AV_RL16(src + 10);
c->status[1].predictor = (int16_t)AV_RL16(src + 12);
c->status[0].step_index = av_clip(src[14], 0, 88);
c->status[1].step_index = av_clip(src[15], 0, 88);
bytestream2_skipu(&gb, 10);
c->status[0].predictor = sign_extend(bytestream2_get_le16u(&gb), 16);
c->status[1].predictor = sign_extend(bytestream2_get_le16u(&gb), 16);
c->status[0].step_index = bytestream2_get_byteu(&gb);
c->status[1].step_index = bytestream2_get_byteu(&gb);
if (c->status[0].step_index > 88u || c->status[1].step_index > 88u){
av_log(avctx, AV_LOG_ERROR, "ERROR: step_index = %i/%i\n",
c->status[0].step_index, c->status[1].step_index);
return AVERROR_INVALIDDATA;
}
/* sign extend the predictors */
src += 16;
diff_channel = c->status[1].predictor;
/* the DK3_GET_NEXT_NIBBLE macro issues the break statement when
* the buffer is consumed */
while (1) {
/* DK3 ADPCM support macro */
#define DK3_GET_NEXT_NIBBLE() \
if (decode_top_nibble_next) { \
nibble = last_byte >> 4; \
decode_top_nibble_next = 0; \
} else { \
last_byte = bytestream2_get_byteu(&gb); \
nibble = last_byte & 0x0F; \
decode_top_nibble_next = 1; \
}
while (samples < samples_end) {
/* for this algorithm, c->status[0] is the sum channel and
* c->status[1] is the diff channel */