From d94728c37728f747baf903f7c96850f8dd040e67 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sat, 10 Jan 2004 01:58:00 +0000 Subject: [PATCH] cleanup Originally committed as revision 2684 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/adpcm.c | 100 +++++++++++++-------------------------------- 1 file changed, 29 insertions(+), 71 deletions(-) diff --git a/libavcodec/adpcm.c b/libavcodec/adpcm.c index 3b5f5c1545..c3ae66effc 100644 --- a/libavcodec/adpcm.c +++ b/libavcodec/adpcm.c @@ -299,7 +299,7 @@ static int adpcm_decode_init(AVCodecContext * avctx) return 0; } -static inline short adpcm_ima_expand_nibble(ADPCMChannelStatus *c, char nibble) +static inline short adpcm_ima_expand_nibble(ADPCMChannelStatus *c, char nibble, int shift) { int step_index; int predictor; @@ -315,34 +315,7 @@ static inline short adpcm_ima_expand_nibble(ADPCMChannelStatus *c, char nibble) /* perform direct multiplication instead of series of jumps proposed by * the reference ADPCM implementation since modern CPUs can do the mults * quickly enough */ - diff = ((2 * delta + 1) * step) >> 3; - predictor = c->predictor; - if (sign) predictor -= diff; - else predictor += diff; - - CLAMP_TO_SHORT(predictor); - c->predictor = predictor; - c->step_index = step_index; - - return (short)predictor; -} - -static inline short adpcm_4xa_expand_nibble(ADPCMChannelStatus *c, char nibble) -{ - int step_index; - int predictor; - int sign, delta, diff, step; - - step = step_table[c->step_index]; - step_index = c->step_index + index_table[(unsigned)nibble]; - if (step_index < 0) step_index = 0; - else if (step_index > 88) step_index = 88; - - sign = nibble & 8; - delta = nibble & 7; - - diff = (delta*step + (step>>1))>>3; // difference to code above - + diff = ((2 * delta + 1) * step) >> shift; predictor = c->predictor; if (sign) predictor -= diff; else predictor += diff; @@ -505,9 +478,9 @@ static int adpcm_decode_frame(AVCodecContext *avctx, samples++; for(m=32; n>0 && m>0; n--, m--) { /* in QuickTime, IMA is encoded by chuncks of 34 bytes (=64 samples) */ - *samples = adpcm_ima_expand_nibble(cs, src[0] & 0x0F); + *samples = adpcm_ima_expand_nibble(cs, src[0] & 0x0F, 3); samples += avctx->channels; - *samples = adpcm_ima_expand_nibble(cs, (src[0] >> 4) & 0x0F); + *samples = adpcm_ima_expand_nibble(cs, (src[0] >> 4) & 0x0F, 3); samples += avctx->channels; src ++; } @@ -524,44 +497,29 @@ static int adpcm_decode_frame(AVCodecContext *avctx, if (avctx->block_align != 0 && buf_size > avctx->block_align) buf_size = avctx->block_align; - // XXX: do as per-channel loop - cs = &(c->status[0]); - cs->predictor = (*src++) & 0x0FF; - cs->predictor |= ((*src++) << 8) & 0x0FF00; - if(cs->predictor & 0x8000) - cs->predictor -= 0x10000; - CLAMP_TO_SHORT(cs->predictor); - - // XXX: is this correct ??: *samples++ = cs->predictor; - - cs->step_index = *src++; - if (cs->step_index < 0) cs->step_index = 0; - if (cs->step_index > 88) cs->step_index = 88; - if (*src++) av_log(avctx, AV_LOG_ERROR, "unused byte should be null !!\n"); /* unused */ - - if (st) { - cs = &(c->status[1]); - cs->predictor = (*src++) & 0x0FF; - cs->predictor |= ((*src++) << 8) & 0x0FF00; + for(i=0; ichannels; i++){ + cs = &(c->status[i]); + cs->predictor = *src++; + cs->predictor |= (*src++) << 8; if(cs->predictor & 0x8000) cs->predictor -= 0x10000; CLAMP_TO_SHORT(cs->predictor); - // XXX: is this correct ??: *samples++ = cs->predictor; + // XXX: is this correct ??: *samples++ = cs->predictor; - cs->step_index = *src++; + cs->step_index = *src++; if (cs->step_index < 0) cs->step_index = 0; if (cs->step_index > 88) cs->step_index = 88; - src++; /* if != 0 -> out-of-sync */ + if (*src++) av_log(avctx, AV_LOG_ERROR, "unused byte should be null !!\n"); /* unused */ } for(m=4; src < (buf + buf_size);) { - *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[0] & 0x0F); + *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[0] & 0x0F, 3); if (st) - *samples++ = adpcm_ima_expand_nibble(&c->status[1], src[4] & 0x0F); - *samples++ = adpcm_ima_expand_nibble(&c->status[0], (src[0] >> 4) & 0x0F); + *samples++ = adpcm_ima_expand_nibble(&c->status[1], src[4] & 0x0F, 3); + *samples++ = adpcm_ima_expand_nibble(&c->status[0], (src[0] >> 4) & 0x0F, 3); if (st) { - *samples++ = adpcm_ima_expand_nibble(&c->status[1], (src[4] >> 4) & 0x0F); + *samples++ = adpcm_ima_expand_nibble(&c->status[1], (src[4] >> 4) & 0x0F, 3); if (!--m) { m=4; src+=4; @@ -585,12 +543,12 @@ static int adpcm_decode_frame(AVCodecContext *avctx, m= (buf_size - (src - buf))>>st; for(i=0; istatus[0], src[i] & 0x0F); + *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[i] & 0x0F, 4); if (st) - *samples++ = adpcm_4xa_expand_nibble(&c->status[1], src[i+m] & 0x0F); - *samples++ = adpcm_4xa_expand_nibble(&c->status[0], src[i] >> 4); + *samples++ = adpcm_ima_expand_nibble(&c->status[1], src[i+m] & 0x0F, 4); + *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[i] >> 4, 4); if (st) - *samples++ = adpcm_4xa_expand_nibble(&c->status[1], src[i+m] >> 4); + *samples++ = adpcm_ima_expand_nibble(&c->status[1], src[i+m] >> 4, 4); } src += m<status[0], - (src[0] >> 4) & 0x0F); + (src[0] >> 4) & 0x0F, 3); /* take care of the bottom nibble, which is right sample for * stereo, or another mono sample */ if (st) *samples++ = adpcm_ima_expand_nibble(&c->status[1], - src[0] & 0x0F); + src[0] & 0x0F, 3); else *samples++ = adpcm_ima_expand_nibble(&c->status[0], - src[0] & 0x0F); + src[0] & 0x0F, 3); src++; } @@ -703,11 +661,11 @@ static int adpcm_decode_frame(AVCodecContext *avctx, /* process the first predictor of the sum channel */ DK3_GET_NEXT_NIBBLE(); - adpcm_ima_expand_nibble(&c->status[0], nibble); + adpcm_ima_expand_nibble(&c->status[0], nibble, 3); /* process the diff channel predictor */ DK3_GET_NEXT_NIBBLE(); - adpcm_ima_expand_nibble(&c->status[1], nibble); + adpcm_ima_expand_nibble(&c->status[1], nibble, 3); /* process the first pair of stereo PCM samples */ diff_channel = (diff_channel + c->status[1].predictor) / 2; @@ -716,7 +674,7 @@ static int adpcm_decode_frame(AVCodecContext *avctx, /* process the second predictor of the sum channel */ DK3_GET_NEXT_NIBBLE(); - adpcm_ima_expand_nibble(&c->status[0], nibble); + adpcm_ima_expand_nibble(&c->status[0], nibble, 3); /* process the second pair of stereo PCM samples */ diff_channel = (diff_channel + c->status[1].predictor) / 2; @@ -730,14 +688,14 @@ static int adpcm_decode_frame(AVCodecContext *avctx, if (st) { *samples++ = adpcm_ima_expand_nibble(&c->status[0], - (src[0] >> 4) & 0x0F); + (src[0] >> 4) & 0x0F, 3); *samples++ = adpcm_ima_expand_nibble(&c->status[1], - src[0] & 0x0F); + src[0] & 0x0F, 3); } else { *samples++ = adpcm_ima_expand_nibble(&c->status[0], - (src[0] >> 4) & 0x0F); + (src[0] >> 4) & 0x0F, 3); *samples++ = adpcm_ima_expand_nibble(&c->status[0], - src[0] & 0x0F); + src[0] & 0x0F, 3); } src++;