* Westwood SNDx codecs
* Copyright (c) 2005 Konstantin Shishkov
*
- * This file is part of Libav.
+ * This file is part of FFmpeg.
*
- * Libav is free software; you can redistribute it and/or
+ * FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
- * Libav is distributed in the hope that it will be useful,
+ * FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with Libav; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
- * Westwood SNDx codecs.
+ * Westwood SNDx codecs
*
* Reference documents about VQA format and its audio codecs
* can be found here:
* http://www.multimedia.cx
*/
-static const int8_t ws_adpcm_2bit[] = { -2, -1, 0, 1};
static const int8_t ws_adpcm_4bit[] = {
-9, -8, -6, -5, -4, -3, -2, -1,
- 0, 1, 2, 3, 4, 5, 6, 8 };
+ 0, 1, 2, 3, 4, 5, 6, 8
+};
-static av_cold int ws_snd_decode_init(AVCodecContext * avctx)
+static av_cold int ws_snd_decode_init(AVCodecContext *avctx)
{
-// WSSNDContext *c = avctx->priv_data;
+ if (avctx->channels != 1) {
+ av_log_ask_for_sample(avctx, "unsupported number of channels\n");
+ return AVERROR(EINVAL);
+ }
avctx->sample_fmt = AV_SAMPLE_FMT_U8;
return 0;
}
-static int ws_snd_decode_frame(AVCodecContext *avctx,
- void *data, int *data_size,
- AVPacket *avpkt)
+static int ws_snd_decode_frame(AVCodecContext *avctx, void *data,
+ int *data_size, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
- int buf_size = avpkt->size;
-// WSSNDContext *c = avctx->priv_data;
+ int buf_size = avpkt->size;
int in_size, out_size;
int sample = 128;
- int i;
uint8_t *samples = data;
+ uint8_t *samples_end;
if (!buf_size)
return 0;
}
out_size = AV_RL16(&buf[0]);
- in_size = AV_RL16(&buf[2]);
+ in_size = AV_RL16(&buf[2]);
buf += 4;
if (out_size > *data_size) {
av_log(avctx, AV_LOG_ERROR, "Frame data is larger than input buffer\n");
return -1;
}
+ samples_end = samples + out_size;
if (in_size == out_size) {
- for (i = 0; i < out_size; i++)
- *samples++ = *buf++;
+ memcpy(samples, buf, out_size);
*data_size = out_size;
return buf_size;
}
- while (out_size > 0 && buf - avpkt->data < buf_size) {
+ while (samples < samples_end && buf - avpkt->data < buf_size) {
int code, smp, size;
uint8_t count;
- code = (*buf) >> 6;
- count = (*buf) & 0x3F;
+ code = *buf >> 6;
+ count = *buf & 0x3F;
buf++;
- /* make sure we don't write more than out_size samples */
+ /* make sure we don't write past the output buffer */
switch (code) {
case 0: smp = 4; break;
case 1: smp = 2; break;
case 2: smp = (count & 0x20) ? 1 : count + 1; break;
default: smp = count + 1; break;
}
- if (out_size < smp) {
- out_size = 0;
+ if (samples_end - samples < smp)
break;
- }
/* make sure we don't read past the input buffer */
size = ((code == 2 && (count & 0x20)) || code == 3) ? 0 : count + 1;
if ((buf - avpkt->data) + size > buf_size)
break;
- switch(code) {
+ switch (code) {
case 0: /* ADPCM 2-bit */
for (count++; count > 0; count--) {
code = *buf++;
- sample += ws_adpcm_2bit[code & 0x3];
+ sample += ( code & 0x3) - 2;
sample = av_clip_uint8(sample);
*samples++ = sample;
- sample += ws_adpcm_2bit[(code >> 2) & 0x3];
+ sample += ((code >> 2) & 0x3) - 2;
sample = av_clip_uint8(sample);
*samples++ = sample;
- sample += ws_adpcm_2bit[(code >> 4) & 0x3];
+ sample += ((code >> 4) & 0x3) - 2;
sample = av_clip_uint8(sample);
*samples++ = sample;
- sample += ws_adpcm_2bit[(code >> 6) & 0x3];
+ sample += (code >> 6) - 2;
sample = av_clip_uint8(sample);
*samples++ = sample;
- out_size -= 4;
}
break;
case 1: /* ADPCM 4-bit */
sample += ws_adpcm_4bit[code >> 4];
sample = av_clip_uint8(sample);
*samples++ = sample;
- out_size -= 2;
}
break;
case 2: /* no compression */
sample += t >> 3;
sample = av_clip_uint8(sample);
*samples++ = sample;
- out_size--;
} else { /* copy */
- for (count++; count > 0; count--) {
- *samples++ = *buf++;
- out_size--;
- }
+ memcpy(samples, buf, smp);
+ samples += smp;
+ buf += smp;
sample = buf[-1];
}
break;
default: /* run */
- for(count++; count > 0; count--) {
- *samples++ = sample;
- out_size--;
- }
+ memset(samples, sample, smp);
+ samples += smp;
}
}
projects / ffmpeg / blobdiff