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4xm adpcm

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Originally committed as revision 1928 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2003-06-03 13:58:44 +00:00
parent c09948b6dc
commit 4b465299f3
4 changed files with 71 additions and 8 deletions
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58
libavcodec/adpcm.c
View File

@ -312,6 +312,33 @@ static inline short adpcm_ima_expand_nibble(ADPCMChannelStatus *c, char nibble)
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
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_ms_expand_nibble(ADPCMChannelStatus *c, char nibble)
{
int predictor;
@ -334,7 +361,7 @@ static int adpcm_decode_frame(AVCodecContext *avctx,
{
ADPCMContext *c = avctx->priv_data;
ADPCMChannelStatus *cs;
int n, m, channel;
int n, m, channel, i;
int block_predictor[2];
short *samples;
uint8_t *src;
@ -444,6 +471,34 @@ static int adpcm_decode_frame(AVCodecContext *avctx,
}
src++;
}
break;
case CODEC_ID_ADPCM_4XM:
cs = &(c->status[0]);
c->status[0].predictor= (int16_t)(src[0] + (src[1]<<8)); src+=2;
if(st){
c->status[1].predictor= (int16_t)(src[0] + (src[1]<<8)); src+=2;
}
c->status[0].step_index= (int16_t)(src[0] + (src[1]<<8)); src+=2;
if(st){
c->status[1].step_index= (int16_t)(src[0] + (src[1]<<8)); src+=2;
}
// if (cs->step_index < 0) cs->step_index = 0;
// if (cs->step_index > 88) cs->step_index = 88;
m= (buf_size - (src - buf))>>st;
//printf("%d %d %d %d\n", st, m, c->status[0].predictor, c->status[0].step_index);
//FIXME / XXX decode chanels individual & interleave samples
for(i=0; i<m; i++) {
*samples++ = adpcm_4xa_expand_nibble(&c->status[0], src[i] & 0x0F);
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);
if (st)
*samples++ = adpcm_4xa_expand_nibble(&c->status[1], src[i+m] >> 4);
}
src += m<<st;
break;
case CODEC_ID_ADPCM_MS:
@ -529,6 +584,7 @@ AVCodec name ## _decoder = { \
ADPCM_CODEC(CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt);
ADPCM_CODEC(CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav);
ADPCM_CODEC(CODEC_ID_ADPCM_MS, adpcm_ms);
ADPCM_CODEC(CODEC_ID_ADPCM_4XM, adpcm_4xm);
#undef ADPCM_CODEC

1
libavcodec/allcodecs.c
View File

@ -133,6 +133,7 @@ PCM_CODEC(CODEC_ID_PCM_MULAW, pcm_mulaw);
PCM_CODEC(CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt);
PCM_CODEC(CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav);
PCM_CODEC(CODEC_ID_ADPCM_MS, adpcm_ms);
PCM_CODEC(CODEC_ID_ADPCM_4XM, adpcm_4xm);
#undef PCM_CODEC
}

1
libavcodec/avcodec.h
View File

@ -1269,6 +1269,7 @@ PCM_CODEC(CODEC_ID_PCM_MULAW, pcm_mulaw);
PCM_CODEC(CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt);
PCM_CODEC(CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav);
PCM_CODEC(CODEC_ID_ADPCM_MS, adpcm_ms);
PCM_CODEC(CODEC_ID_ADPCM_4XM, adpcm_4xm);
#undef PCM_CODEC

19
libavformat/4xm.c
View File

@ -71,6 +71,7 @@ typedef struct AudioTrack {
int bits;
int channels;
int stream_index;
int adpcm;
} AudioTrack;
typedef struct FourxmDemuxContext {
@ -172,9 +173,11 @@ static int fourxm_read_header(AVFormatContext *s,
return AVERROR_NOMEM;
}
}
fourxm->tracks[current_track].adpcm = LE_32(&header[i + 12]);
fourxm->tracks[current_track].channels = LE_32(&header[i + 36]);
fourxm->tracks[current_track].sample_rate = LE_32(&header[i + 40]);
fourxm->tracks[current_track].bits = LE_32(&header[i + 44]);
printf("bps:%d\n", fourxm->tracks[current_track].bits);
i += 8 + size;
/* allocate a new AVStream */
@ -192,7 +195,9 @@ static int fourxm_read_header(AVFormatContext *s,
st->codec.bit_rate = st->codec.channels * st->codec.sample_rate *
st->codec.bits_per_sample;
st->codec.block_align = st->codec.channels * st->codec.bits_per_sample;
if (st->codec.bits_per_sample == 8)
if (fourxm->tracks[current_track].adpcm)
st->codec.codec_id = CODEC_ID_ADPCM_4XM;
else if (st->codec.bits_per_sample == 8)
st->codec.codec_id = CODEC_ID_PCM_U8;
else
st->codec.codec_id = CODEC_ID_PCM_S16LE;
@ -224,7 +229,7 @@ static int fourxm_read_packet(AVFormatContext *s,
FourxmDemuxContext *fourxm = s->priv_data;
ByteIOContext *pb = &s->pb;
unsigned int fourcc_tag;
unsigned int size;
unsigned int size, out_size;
int ret = 0;
int track_number;
int packet_read = 0;
@ -237,10 +242,9 @@ static int fourxm_read_packet(AVFormatContext *s,
return ret;
fourcc_tag = LE_32(&header[0]);
size = LE_32(&header[4]);
//printf(" %8X %c%c%c%c %d\n", fourcc_tag, fourcc_tag, fourcc_tag>>8, fourcc_tag>>16, fourcc_tag>>24, size);
if (url_feof(pb))
return -EIO;
switch (fourcc_tag) {
case LIST_TAG:
@ -277,7 +281,7 @@ if (fourcc_tag == cfrm_TAG) {
id = LE_32(&pkt->data[12]);
whole = LE_32(&pkt->data[16]);
stats[id] += size - 12;
printf(" cfrm chunk id:%d size:%d whole:%d until now:%d\n", id, size, whole, stats[id]);
//printf(" cfrm chunk id:%d size:%d whole:%d until now:%d\n", id, size, whole, stats[id]);
}
if (ret < 0)
@ -290,7 +294,9 @@ printf(" cfrm chunk id:%d size:%d whole:%d until now:%d\n", id, size, whole, sta
case snd__TAG:
printf (" snd_ chunk, ");
track_number = get_le32(pb);
size = get_le32(pb);
out_size= get_le32(pb);
size-=8;
if (track_number == fourxm->selected_track) {
printf ("correct track, dispatching...\n");
if (av_new_packet(pkt, size))
@ -321,7 +327,6 @@ printf ("wrong track, skipping...\n");
break;
}
}
return ret;
}