* Assorted DPCM codecs
* Copyright (c) 2003 The ffmpeg Project
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav 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.
*
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav 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 FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
+#include "bytestream.h"
+#include "internal.h"
+#include "mathops.h"
typedef struct DPCMContext {
- int channels;
- short roq_square_array[256];
- long sample[2];//for SOL_DPCM
- const int *sol_table;//for SOL_DPCM
+ int16_t roq_square_array[256];
+ int sample[2]; ///< previous sample (for SOL_DPCM)
+ const int8_t *sol_table; ///< delta table for SOL_DPCM
} DPCMContext;
-#define SE_16BIT(x) if (x & 0x8000) x -= 0x10000;
-
-static const int interplay_delta_table[] = {
+static const int16_t interplay_delta_table[] = {
0, 1, 2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12, 13, 14, 15,
16, 17, 18, 19, 20, 21, 22, 23,
};
-static const int sol_table_old[16] =
- { 0x0, 0x1, 0x2 , 0x3, 0x6, 0xA, 0xF, 0x15,
- -0x15, -0xF, -0xA, -0x6, -0x3, -0x2, -0x1, 0x0};
+static const int8_t sol_table_old[16] = {
+ 0x0, 0x1, 0x2, 0x3, 0x6, 0xA, 0xF, 0x15,
+ -0x15, -0xF, -0xA, -0x6, -0x3, -0x2, -0x1, 0x0
+};
-static const int sol_table_new[16] =
- { 0x0, 0x1, 0x2, 0x3, 0x6, 0xA, 0xF, 0x15,
- 0x0, -0x1, -0x2, -0x3, -0x6, -0xA, -0xF, -0x15};
+static const int8_t sol_table_new[16] = {
+ 0x0, 0x1, 0x2, 0x3, 0x6, 0xA, 0xF, 0x15,
+ 0x0, -0x1, -0x2, -0x3, -0x6, -0xA, -0xF, -0x15
+};
-static const int sol_table_16[128] = {
+static const int16_t sol_table_16[128] = {
0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080,
0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120,
0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0,
};
-
static av_cold int dpcm_decode_init(AVCodecContext *avctx)
{
DPCMContext *s = avctx->priv_data;
int i;
- short square;
- s->channels = avctx->channels;
+ if (avctx->channels < 1 || avctx->channels > 2) {
+ av_log(avctx, AV_LOG_INFO, "invalid number of channels\n");
+ return AVERROR(EINVAL);
+ }
+
s->sample[0] = s->sample[1] = 0;
switch(avctx->codec->id) {
- case CODEC_ID_ROQ_DPCM:
+ case AV_CODEC_ID_ROQ_DPCM:
/* initialize square table */
for (i = 0; i < 128; i++) {
- square = i * i;
- s->roq_square_array[i] = square;
+ int16_t square = i * i;
+ s->roq_square_array[i ] = square;
s->roq_square_array[i + 128] = -square;
}
break;
-
- case CODEC_ID_SOL_DPCM:
+ case AV_CODEC_ID_SOL_DPCM:
switch(avctx->codec_tag){
case 1:
- s->sol_table=sol_table_old;
+ s->sol_table = sol_table_old;
s->sample[0] = s->sample[1] = 0x80;
break;
case 2:
- s->sol_table=sol_table_new;
+ s->sol_table = sol_table_new;
s->sample[0] = s->sample[1] = 0x80;
break;
case 3:
- s->sol_table=sol_table_16;
break;
default:
av_log(avctx, AV_LOG_ERROR, "Unknown SOL subcodec\n");
break;
}
- avctx->sample_fmt = AV_SAMPLE_FMT_S16;
+ if (avctx->codec->id == AV_CODEC_ID_SOL_DPCM && avctx->codec_tag != 3)
+ avctx->sample_fmt = AV_SAMPLE_FMT_U8;
+ else
+ avctx->sample_fmt = AV_SAMPLE_FMT_S16;
+
return 0;
}
-static int dpcm_decode_frame(AVCodecContext *avctx,
- void *data, int *data_size,
- AVPacket *avpkt)
+
+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;
DPCMContext *s = avctx->priv_data;
- int in, out = 0;
+ AVFrame *frame = data;
+ int out = 0, ret;
int predictor[2];
- int channel_number = 0;
- short *output_samples = data;
- int shift[2];
- unsigned char byte;
- short diff;
+ int ch = 0;
+ int stereo = avctx->channels - 1;
+ int16_t *output_samples, *samples_end;
+ GetByteContext gb;
+
+ if (stereo && (buf_size & 1))
+ buf_size--;
+ bytestream2_init(&gb, avpkt->data, buf_size);
- if (!buf_size)
- return 0;
+ /* calculate output size */
+ switch(avctx->codec->id) {
+ case AV_CODEC_ID_ROQ_DPCM:
+ out = buf_size - 8;
+ break;
+ case AV_CODEC_ID_INTERPLAY_DPCM:
+ out = buf_size - 6 - avctx->channels;
+ break;
+ case AV_CODEC_ID_XAN_DPCM:
+ out = buf_size - 2 * avctx->channels;
+ break;
+ case AV_CODEC_ID_SOL_DPCM:
+ if (avctx->codec_tag != 3)
+ out = buf_size * 2;
+ else
+ out = buf_size;
+ break;
+ }
+ if (out <= 0) {
+ av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
+ return AVERROR(EINVAL);
+ }
- // almost every DPCM variant expands one byte of data into two
- if(*data_size/2 < buf_size)
- return -1;
+ /* get output buffer */
+ frame->nb_samples = out / avctx->channels;
+ if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
+ av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+ return ret;
+ }
+ output_samples = (int16_t *)frame->data[0];
+ samples_end = output_samples + out;
switch(avctx->codec->id) {
- case CODEC_ID_ROQ_DPCM:
- if (s->channels == 1)
- predictor[0] = AV_RL16(&buf[6]);
- else {
- predictor[0] = buf[7] << 8;
- predictor[1] = buf[6] << 8;
+ case AV_CODEC_ID_ROQ_DPCM:
+ bytestream2_skipu(&gb, 6);
+
+ if (stereo) {
+ predictor[1] = sign_extend(bytestream2_get_byteu(&gb) << 8, 16);
+ predictor[0] = sign_extend(bytestream2_get_byteu(&gb) << 8, 16);
+ } else {
+ predictor[0] = sign_extend(bytestream2_get_le16u(&gb), 16);
}
- SE_16BIT(predictor[0]);
- SE_16BIT(predictor[1]);
/* decode the samples */
- for (in = 8, out = 0; in < buf_size; in++, out++) {
- predictor[channel_number] += s->roq_square_array[buf[in]];
- predictor[channel_number] = av_clip_int16(predictor[channel_number]);
- output_samples[out] = predictor[channel_number];
+ 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];
/* toggle channel */
- channel_number ^= s->channels - 1;
+ ch ^= stereo;
}
break;
- case CODEC_ID_INTERPLAY_DPCM:
- in = 6; /* skip over the stream mask and stream length */
- predictor[0] = AV_RL16(&buf[in]);
- in += 2;
- SE_16BIT(predictor[0])
- output_samples[out++] = predictor[0];
- if (s->channels == 2) {
- predictor[1] = AV_RL16(&buf[in]);
- in += 2;
- SE_16BIT(predictor[1])
- output_samples[out++] = predictor[1];
+ case AV_CODEC_ID_INTERPLAY_DPCM:
+ bytestream2_skipu(&gb, 6); /* skip over the stream mask and stream length */
+
+ for (ch = 0; ch < avctx->channels; ch++) {
+ predictor[ch] = sign_extend(bytestream2_get_le16u(&gb), 16);
+ *output_samples++ = predictor[ch];
}
- while (in < buf_size) {
- predictor[channel_number] += interplay_delta_table[buf[in++]];
- predictor[channel_number] = av_clip_int16(predictor[channel_number]);
- output_samples[out++] = predictor[channel_number];
+ ch = 0;
+ 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];
/* toggle channel */
- channel_number ^= s->channels - 1;
+ ch ^= stereo;
}
-
break;
- case CODEC_ID_XAN_DPCM:
- in = 0;
- shift[0] = shift[1] = 4;
- predictor[0] = AV_RL16(&buf[in]);
- in += 2;
- SE_16BIT(predictor[0]);
- if (s->channels == 2) {
- predictor[1] = AV_RL16(&buf[in]);
- in += 2;
- SE_16BIT(predictor[1]);
- }
+ case AV_CODEC_ID_XAN_DPCM:
+ {
+ int shift[2] = { 4, 4 };
- while (in < buf_size) {
- byte = buf[in++];
- diff = (byte & 0xFC) << 8;
- if ((byte & 0x03) == 3)
- shift[channel_number]++;
+ for (ch = 0; ch < avctx->channels; ch++)
+ predictor[ch] = sign_extend(bytestream2_get_le16u(&gb), 16);
+
+ ch = 0;
+ while (output_samples < samples_end) {
+ int diff = bytestream2_get_byteu(&gb);
+ int n = diff & 3;
+
+ if (n == 3)
+ shift[ch]++;
else
- shift[channel_number] -= (2 * (byte & 3));
+ shift[ch] -= (2 * n);
+ diff = sign_extend((diff &~ 3) << 8, 16);
+
/* saturate the shifter to a lower limit of 0 */
- if (shift[channel_number] < 0)
- shift[channel_number] = 0;
+ if (shift[ch] < 0)
+ shift[ch] = 0;
- diff >>= shift[channel_number];
- predictor[channel_number] += diff;
+ diff >>= shift[ch];
+ predictor[ch] += diff;
- predictor[channel_number] = av_clip_int16(predictor[channel_number]);
- output_samples[out++] = predictor[channel_number];
+ predictor[ch] = av_clip_int16(predictor[ch]);
+ *output_samples++ = predictor[ch];
/* toggle channel */
- channel_number ^= s->channels - 1;
+ ch ^= stereo;
}
break;
- case CODEC_ID_SOL_DPCM:
- in = 0;
+ }
+ case AV_CODEC_ID_SOL_DPCM:
if (avctx->codec_tag != 3) {
- if(*data_size/4 < buf_size)
- return -1;
- while (in < buf_size) {
- int n1, n2;
- n1 = (buf[in] >> 4) & 0xF;
- n2 = buf[in++] & 0xF;
- s->sample[0] += s->sol_table[n1];
- if (s->sample[0] < 0) s->sample[0] = 0;
- if (s->sample[0] > 255) s->sample[0] = 255;
- output_samples[out++] = (s->sample[0] - 128) << 8;
- s->sample[s->channels - 1] += s->sol_table[n2];
- if (s->sample[s->channels - 1] < 0) s->sample[s->channels - 1] = 0;
- if (s->sample[s->channels - 1] > 255) s->sample[s->channels - 1] = 255;
- output_samples[out++] = (s->sample[s->channels - 1] - 128) << 8;
+ uint8_t *output_samples_u8 = 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]);
+ *output_samples_u8++ = s->sample[0];
+
+ s->sample[stereo] += s->sol_table[n & 0x0F];
+ s->sample[stereo] = av_clip_uint8(s->sample[stereo]);
+ *output_samples_u8++ = s->sample[stereo];
}
} else {
- while (in < buf_size) {
- int n;
- n = buf[in++];
- if (n & 0x80) s->sample[channel_number] -= s->sol_table[n & 0x7F];
- else s->sample[channel_number] += s->sol_table[n & 0x7F];
- s->sample[channel_number] = av_clip_int16(s->sample[channel_number]);
- output_samples[out++] = s->sample[channel_number];
+ 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]);
+ *output_samples++ = s->sample[ch];
/* toggle channel */
- channel_number ^= s->channels - 1;
+ ch ^= stereo;
}
}
break;
}
- *data_size = out * sizeof(short);
- return buf_size;
+ *got_frame_ptr = 1;
+
+ return avpkt->size;
}
-#define DPCM_DECODER(id, name, long_name_) \
-AVCodec name ## _decoder = { \
- #name, \
- AVMEDIA_TYPE_AUDIO, \
- id, \
- sizeof(DPCMContext), \
- dpcm_decode_init, \
- NULL, \
- NULL, \
- dpcm_decode_frame, \
- .long_name = NULL_IF_CONFIG_SMALL(long_name_), \
-};
+#define DPCM_DECODER(id_, name_, long_name_) \
+AVCodec ff_ ## name_ ## _decoder = { \
+ .name = #name_, \
+ .type = AVMEDIA_TYPE_AUDIO, \
+ .id = id_, \
+ .priv_data_size = sizeof(DPCMContext), \
+ .init = dpcm_decode_init, \
+ .decode = dpcm_decode_frame, \
+ .capabilities = CODEC_CAP_DR1, \
+ .long_name = NULL_IF_CONFIG_SMALL(long_name_), \
+}
-DPCM_DECODER(CODEC_ID_INTERPLAY_DPCM, interplay_dpcm, "DPCM Interplay");
-DPCM_DECODER(CODEC_ID_ROQ_DPCM, roq_dpcm, "DPCM id RoQ");
-DPCM_DECODER(CODEC_ID_SOL_DPCM, sol_dpcm, "DPCM Sol");
-DPCM_DECODER(CODEC_ID_XAN_DPCM, xan_dpcm, "DPCM Xan");
+DPCM_DECODER(AV_CODEC_ID_INTERPLAY_DPCM, interplay_dpcm, "DPCM Interplay");
+DPCM_DECODER(AV_CODEC_ID_ROQ_DPCM, roq_dpcm, "DPCM id RoQ");
+DPCM_DECODER(AV_CODEC_ID_SOL_DPCM, sol_dpcm, "DPCM Sol");
+DPCM_DECODER(AV_CODEC_ID_XAN_DPCM, xan_dpcm, "DPCM Xan");