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avcodec/adpcm_argo: simplify and move duplicated logic into a function 

Signed-off-by: Zane van Iperen <zane@zanevaniperen.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Zane van Iperen 2020-02-01 06:59:59 +00:00 committed by Michael Niedermayer
parent cd823dadf9
commit b49404ea30
1 changed files with 18 additions and 22 deletions
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40
libavcodec/adpcm.c
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@ -552,9 +552,21 @@ static void adpcm_swf_decode(AVCodecContext *avctx, const uint8_t *buf, int buf_
}
}
static inline int16_t adpcm_argo_expand_nibble(int nibble, int shift, int16_t prev0, int16_t prev1)
static inline int16_t adpcm_argo_expand_nibble(ADPCMChannelStatus *cs, int nibble, int control, int shift)
{
return ((8 * prev0) - (4 * prev1) + (nibble * (1 << shift))) >> 2;
int sample = nibble * (1 << shift);
if (control & 0x04)
sample += (8 * cs->sample1) - (4 * cs->sample2);
else
sample += 4 * cs->sample1;
sample = av_clip_int16(sample >> 2);
cs->sample2 = cs->sample1;
cs->sample1 = sample;
return sample;
}
/**
@ -1805,7 +1817,7 @@ static int adpcm_decode_frame(AVCodecContext *avctx, void *data,
* They should be 0 initially.
*/
for (channel = 0; channel < avctx->channels; channel++) {
int control, shift, sample, nibble;
int control, shift;
samples = samples_p[channel];
cs = c->status + channel;
@ -1815,25 +1827,9 @@ static int adpcm_decode_frame(AVCodecContext *avctx, void *data,
shift = (control >> 4) + 2;
for (n = 0; n < nb_samples / 2; n++) {
sample = bytestream2_get_byteu(&gb);
nibble = sign_extend(sample >> 4, 4);
if (control & 0x04)
*samples = adpcm_argo_expand_nibble(nibble, shift, cs->sample1, cs->sample2);
else
*samples = adpcm_argo_expand_nibble(nibble, shift, cs->sample1, cs->sample1);
cs->sample2 = cs->sample1;
cs->sample1 = *samples++;
nibble = sign_extend(sample >> 0, 4);
if (control & 0x04)
*samples = adpcm_argo_expand_nibble(nibble, shift, cs->sample1, cs->sample2);
else
*samples = adpcm_argo_expand_nibble(nibble, shift, cs->sample1, cs->sample1);
cs->sample2 = cs->sample1;
cs->sample1 = *samples++;
int sample = bytestream2_get_byteu(&gb);
*samples++ = adpcm_argo_expand_nibble(cs, sign_extend(sample >> 4, 4), control, shift);
*samples++ = adpcm_argo_expand_nibble(cs, sign_extend(sample >> 0, 4), control, shift);
}
}
break;