virtualenv/FFmpeg
1
0
Fork 0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-11-21 10:55:51 +02:00
Code Issues Releases Activity

dpcm: convert to bytestream2.

Browse Source
This commit is contained in:
Ronald S. Bultje 2012-03-18 19:33:04 -07:00
parent f31a68e78c
commit 3a3f06b05e
1 changed files with 31 additions and 27 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

58
libavcodec/dpcm.c
View File

@ -40,6 +40,7 @@
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "bytestream.h"
#include "mathops.h"
typedef struct DPCMContext {
AVFrame frame;
@ -173,20 +174,18 @@ static av_cold int dpcm_decode_init(AVCodecContext *avctx)
static int dpcm_decode_frame(AVCodecContext *avctx, void *data,
int *got_frame_ptr, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
const uint8_t *buf_end = buf + buf_size;
DPCMContext *s = avctx->priv_data;
int out = 0, ret;
int predictor[2];
int ch = 0;
int stereo = s->channels - 1;
int16_t *output_samples;
int16_t *output_samples, *samples_end;
GetByteContext gb;
if (stereo && (buf_size & 1)) {
if (stereo && (buf_size & 1))
buf_size--;
buf_end--;
}
bytestream2_init(&gb, avpkt->data, buf_size);
/* calculate output size */
switch(avctx->codec->id) {
@ -218,22 +217,23 @@ static int dpcm_decode_frame(AVCodecContext *avctx, void *data,
return ret;
}
output_samples = (int16_t *)s->frame.data[0];
samples_end = output_samples + out;
switch(avctx->codec->id) {
case CODEC_ID_ROQ_DPCM:
buf += 6;
bytestream2_skipu(&gb, 6);
if (stereo) {
predictor[1] = (int16_t)(bytestream_get_byte(&buf) << 8);
predictor[0] = (int16_t)(bytestream_get_byte(&buf) << 8);
predictor[1] = sign_extend(bytestream2_get_byteu(&gb) << 8, 16);
predictor[0] = sign_extend(bytestream2_get_byteu(&gb) << 8, 16);
} else {
predictor[0] = (int16_t)bytestream_get_le16(&buf);
predictor[0] = sign_extend(bytestream2_get_le16u(&gb), 16);
}
/* decode the samples */
while (buf < buf_end) {
predictor[ch] += s->roq_square_array[*buf++];
while (output_samples < samples_end) {
predictor[ch] += s->roq_square_array[bytestream2_get_byteu(&gb)];
predictor[ch] = av_clip_int16(predictor[ch]);
*output_samples++ = predictor[ch];
@ -243,16 +243,16 @@ static int dpcm_decode_frame(AVCodecContext *avctx, void *data,
break;
case CODEC_ID_INTERPLAY_DPCM:
buf += 6; /* skip over the stream mask and stream length */
bytestream2_skipu(&gb, 6); /* skip over the stream mask and stream length */
for (ch = 0; ch < s->channels; ch++) {
predictor[ch] = (int16_t)bytestream_get_le16(&buf);
predictor[ch] = sign_extend(bytestream2_get_le16u(&gb), 16);
*output_samples++ = predictor[ch];
}
ch = 0;
while (buf < buf_end) {
predictor[ch] += interplay_delta_table[*buf++];
while (output_samples < samples_end) {
predictor[ch] += interplay_delta_table[bytestream2_get_byteu(&gb)];
predictor[ch] = av_clip_int16(predictor[ch]);
*output_samples++ = predictor[ch];
@ -266,16 +266,19 @@ static int dpcm_decode_frame(AVCodecContext *avctx, void *data,
int shift[2] = { 4, 4 };
for (ch = 0; ch < s->channels; ch++)
predictor[ch] = (int16_t)bytestream_get_le16(&buf);
predictor[ch] = sign_extend(bytestream2_get_le16u(&gb), 16);
ch = 0;
while (buf < buf_end) {
uint8_t n = *buf++;
int16_t diff = (n & 0xFC) << 8;
if ((n & 0x03) == 3)
while (output_samples < samples_end) {
int diff = bytestream2_get_byteu(&gb);
int n = diff & 3;
if (n == 3)
shift[ch]++;
else
shift[ch] -= (2 * (n & 3));
shift[ch] -= (2 * n);
diff = sign_extend((diff &~ 3) << 8, 16);
/* saturate the shifter to a lower limit of 0 */
if (shift[ch] < 0)
shift[ch] = 0;
@ -293,9 +296,10 @@ static int dpcm_decode_frame(AVCodecContext *avctx, void *data,
}
case CODEC_ID_SOL_DPCM:
if (avctx->codec_tag != 3) {
uint8_t *output_samples_u8 = s->frame.data[0];
while (buf < buf_end) {
uint8_t n = *buf++;
uint8_t *output_samples_u8 = s->frame.data[0],
*samples_end_u8 = output_samples_u8 + out;
while (output_samples_u8 < samples_end_u8) {
int n = bytestream2_get_byteu(&gb);
s->sample[0] += s->sol_table[n >> 4];
s->sample[0] = av_clip_uint8(s->sample[0]);
@ -306,8 +310,8 @@ static int dpcm_decode_frame(AVCodecContext *avctx, void *data,
*output_samples_u8++ = s->sample[stereo];
}
} else {
while (buf < buf_end) {
uint8_t n = *buf++;
while (output_samples < samples_end) {
int n = bytestream2_get_byteu(&gb);
if (n & 0x80) s->sample[ch] -= sol_table_16[n & 0x7F];
else s->sample[ch] += sol_table_16[n & 0x7F];
s->sample[ch] = av_clip_int16(s->sample[ch]);