2 * Sierra VMD Audio & Video Decoders
3 * Copyright (C) 2004 the ffmpeg project
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 * Sierra VMD audio & video decoders
25 * by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
26 * for more information on the Sierra VMD format, visit:
27 * http://www.pcisys.net/~melanson/codecs/
29 * The video decoder outputs PAL8 colorspace data. The decoder expects
30 * a 0x330-byte VMD file header to be transmitted via extradata during
31 * codec initialization. Each encoded frame that is sent to this decoder
32 * is expected to be prepended with the appropriate 16-byte frame
33 * information record from the VMD file.
35 * The audio decoder, like the video decoder, expects each encoded data
36 * chunk to be prepended with the appropriate 16-byte frame information
37 * record from the VMD file. It does not require the 0x330-byte VMD file
38 * header, but it does need the audio setup parameters passed in through
39 * normal libavcodec API means.
46 #include "libavutil/common.h"
47 #include "libavutil/intreadwrite.h"
50 #define VMD_HEADER_SIZE 0x330
51 #define PALETTE_COUNT 256
57 typedef struct VmdVideoContext {
59 AVCodecContext *avctx;
63 const unsigned char *buf;
66 unsigned char palette[PALETTE_COUNT * 4];
67 unsigned char *unpack_buffer;
68 int unpack_buffer_size;
73 #define QUEUE_SIZE 0x1000
74 #define QUEUE_MASK 0x0FFF
76 static void lz_unpack(const unsigned char *src, int src_len,
77 unsigned char *dest, int dest_len)
79 const unsigned char *s;
80 const unsigned char *s_end;
83 unsigned char queue[QUEUE_SIZE];
85 unsigned int dataleft;
86 unsigned int chainofs;
87 unsigned int chainlen;
93 s_end = src + src_len;
99 dataleft = AV_RL32(s);
101 memset(queue, 0x20, QUEUE_SIZE);
102 if (AV_RL32(s) == 0x56781234) {
108 speclen = 100; /* no speclen */
111 while (s_end - s > 0 && dataleft > 0) {
113 if ((tag == 0xFF) && (dataleft > 8)) {
114 if (d_end - d < 8 || s_end - s < 8)
116 for (i = 0; i < 8; i++) {
117 queue[qpos++] = *d++ = *s++;
122 for (i = 0; i < 8; i++) {
126 if (d_end - d < 1 || s_end - s < 1)
128 queue[qpos++] = *d++ = *s++;
135 chainofs |= ((*s & 0xF0) << 4);
136 chainlen = (*s++ & 0x0F) + 3;
137 if (chainlen == speclen) {
140 chainlen = *s++ + 0xF + 3;
142 if (d_end - d < chainlen)
144 for (j = 0; j < chainlen; j++) {
145 *d = queue[chainofs++ & QUEUE_MASK];
146 queue[qpos++] = *d++;
149 dataleft -= chainlen;
157 static int rle_unpack(const unsigned char *src, int src_len, int src_count,
158 unsigned char *dest, int dest_len)
160 const unsigned char *ps;
161 const unsigned char *ps_end;
164 unsigned char *dest_end = dest + dest_len;
167 ps_end = src + src_len;
183 if (dest_end - pd < l || ps_end - ps < l)
189 if (dest_end - pd < i || ps_end - ps < 2)
191 for (i = 0; i < l; i++) {
198 } while (i < src_count);
203 static void vmd_decode(VmdVideoContext *s)
206 unsigned int *palette32;
207 unsigned char r, g, b;
209 /* point to the start of the encoded data */
210 const unsigned char *p = s->buf + 16;
211 const unsigned char *p_end = s->buf + s->size;
213 const unsigned char *pb;
214 const unsigned char *pb_end;
216 unsigned char *dp; /* pointer to current frame */
217 unsigned char *pp; /* pointer to previous frame */
221 int frame_x, frame_y;
222 int frame_width, frame_height;
224 frame_x = AV_RL16(&s->buf[6]);
225 frame_y = AV_RL16(&s->buf[8]);
226 frame_width = AV_RL16(&s->buf[10]) - frame_x + 1;
227 frame_height = AV_RL16(&s->buf[12]) - frame_y + 1;
228 if (frame_x < 0 || frame_width < 0 ||
229 frame_x >= s->avctx->width ||
230 frame_width > s->avctx->width ||
231 frame_x + frame_width > s->avctx->width)
233 if (frame_y < 0 || frame_height < 0 ||
234 frame_y >= s->avctx->height ||
235 frame_height > s->avctx->height ||
236 frame_y + frame_height > s->avctx->height)
239 if ((frame_width == s->avctx->width && frame_height == s->avctx->height) &&
240 (frame_x || frame_y)) {
248 /* if only a certain region will be updated, copy the entire previous
249 * frame before the decode */
250 if (s->prev_frame.data[0] &&
251 (frame_x || frame_y || (frame_width != s->avctx->width) ||
252 (frame_height != s->avctx->height))) {
254 memcpy(s->frame.data[0], s->prev_frame.data[0],
255 s->avctx->height * s->frame.linesize[0]);
258 /* check if there is a new palette */
259 if (s->buf[15] & 0x02) {
260 if (p_end - p < 2 + 3 * PALETTE_COUNT)
263 palette32 = (unsigned int *)s->palette;
264 for (i = 0; i < PALETTE_COUNT; i++) {
268 palette32[i] = 0xFF << 24 | r << 16 | g << 8 | b;
269 palette32[i] |= palette32[i] >> 6 & 0x30303;
273 /* originally UnpackFrame in VAG's code */
278 lz_unpack(pb, p_end - pb, s->unpack_buffer, s->unpack_buffer_size);
280 pb = s->unpack_buffer;
281 pb_end = s->unpack_buffer + s->unpack_buffer_size;
284 dp = &s->frame.data[0][frame_y * s->frame.linesize[0] + frame_x];
285 pp = &s->prev_frame.data[0][frame_y * s->prev_frame.linesize[0] + frame_x];
288 for (i = 0; i < frame_height; i++) {
295 len = (len & 0x7F) + 1;
296 if (ofs + len > frame_width || pb_end - pb < len)
298 memcpy(&dp[ofs], pb, len);
302 /* interframe pixel copy */
303 if (ofs + len + 1 > frame_width || !s->prev_frame.data[0])
305 memcpy(&dp[ofs], &pp[ofs], len + 1);
308 } while (ofs < frame_width);
309 if (ofs > frame_width) {
310 av_log(s->avctx, AV_LOG_ERROR, "offset > width (%d > %d)\n",
314 dp += s->frame.linesize[0];
315 pp += s->prev_frame.linesize[0];
320 for (i = 0; i < frame_height; i++) {
321 if (pb_end -pb < frame_width)
323 memcpy(dp, pb, frame_width);
325 dp += s->frame.linesize[0];
326 pp += s->prev_frame.linesize[0];
331 for (i = 0; i < frame_height; i++) {
338 len = (len & 0x7F) + 1;
342 len = rle_unpack(pb, pb_end - pb, len, &dp[ofs], frame_width - ofs);
344 if (pb_end - pb < len)
346 memcpy(&dp[ofs], pb, len);
351 /* interframe pixel copy */
352 if (ofs + len + 1 > frame_width || !s->prev_frame.data[0])
354 memcpy(&dp[ofs], &pp[ofs], len + 1);
357 } while (ofs < frame_width);
358 if (ofs > frame_width) {
359 av_log(s->avctx, AV_LOG_ERROR, "offset > width (%d > %d)\n",
362 dp += s->frame.linesize[0];
363 pp += s->prev_frame.linesize[0];
370 static av_cold int vmdvideo_decode_init(AVCodecContext *avctx)
372 VmdVideoContext *s = avctx->priv_data;
374 unsigned int *palette32;
375 int palette_index = 0;
376 unsigned char r, g, b;
377 unsigned char *vmd_header;
378 unsigned char *raw_palette;
381 avctx->pix_fmt = PIX_FMT_PAL8;
383 /* make sure the VMD header made it */
384 if (s->avctx->extradata_size != VMD_HEADER_SIZE) {
385 av_log(s->avctx, AV_LOG_ERROR, "expected extradata size of %d\n",
389 vmd_header = (unsigned char *)avctx->extradata;
391 s->unpack_buffer_size = AV_RL32(&vmd_header[800]);
392 s->unpack_buffer = av_malloc(s->unpack_buffer_size);
393 if (!s->unpack_buffer)
396 /* load up the initial palette */
397 raw_palette = &vmd_header[28];
398 palette32 = (unsigned int *)s->palette;
399 for (i = 0; i < PALETTE_COUNT; i++) {
400 r = raw_palette[palette_index++] * 4;
401 g = raw_palette[palette_index++] * 4;
402 b = raw_palette[palette_index++] * 4;
403 palette32[i] = (r << 16) | (g << 8) | (b);
406 avcodec_get_frame_defaults(&s->frame);
407 avcodec_get_frame_defaults(&s->prev_frame);
412 static int vmdvideo_decode_frame(AVCodecContext *avctx,
413 void *data, int *data_size,
416 const uint8_t *buf = avpkt->data;
417 int buf_size = avpkt->size;
418 VmdVideoContext *s = avctx->priv_data;
426 s->frame.reference = 3;
427 if (avctx->get_buffer(avctx, &s->frame)) {
428 av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed\n");
434 /* make the palette available on the way out */
435 memcpy(s->frame.data[1], s->palette, PALETTE_COUNT * 4);
438 FFSWAP(AVFrame, s->frame, s->prev_frame);
439 if (s->frame.data[0])
440 avctx->release_buffer(avctx, &s->frame);
442 *data_size = sizeof(AVFrame);
443 *(AVFrame*)data = s->prev_frame;
445 /* report that the buffer was completely consumed */
449 static av_cold int vmdvideo_decode_end(AVCodecContext *avctx)
451 VmdVideoContext *s = avctx->priv_data;
453 if (s->prev_frame.data[0])
454 avctx->release_buffer(avctx, &s->prev_frame);
455 av_free(s->unpack_buffer);
465 #define BLOCK_TYPE_AUDIO 1
466 #define BLOCK_TYPE_INITIAL 2
467 #define BLOCK_TYPE_SILENCE 3
469 typedef struct VmdAudioContext {
475 static const uint16_t vmdaudio_table[128] = {
476 0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080,
477 0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120,
478 0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0,
479 0x1D0, 0x1E0, 0x1F0, 0x200, 0x208, 0x210, 0x218, 0x220, 0x228, 0x230,
480 0x238, 0x240, 0x248, 0x250, 0x258, 0x260, 0x268, 0x270, 0x278, 0x280,
481 0x288, 0x290, 0x298, 0x2A0, 0x2A8, 0x2B0, 0x2B8, 0x2C0, 0x2C8, 0x2D0,
482 0x2D8, 0x2E0, 0x2E8, 0x2F0, 0x2F8, 0x300, 0x308, 0x310, 0x318, 0x320,
483 0x328, 0x330, 0x338, 0x340, 0x348, 0x350, 0x358, 0x360, 0x368, 0x370,
484 0x378, 0x380, 0x388, 0x390, 0x398, 0x3A0, 0x3A8, 0x3B0, 0x3B8, 0x3C0,
485 0x3C8, 0x3D0, 0x3D8, 0x3E0, 0x3E8, 0x3F0, 0x3F8, 0x400, 0x440, 0x480,
486 0x4C0, 0x500, 0x540, 0x580, 0x5C0, 0x600, 0x640, 0x680, 0x6C0, 0x700,
487 0x740, 0x780, 0x7C0, 0x800, 0x900, 0xA00, 0xB00, 0xC00, 0xD00, 0xE00,
488 0xF00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x3000, 0x4000
491 static av_cold int vmdaudio_decode_init(AVCodecContext *avctx)
493 VmdAudioContext *s = avctx->priv_data;
495 if (avctx->channels < 1 || avctx->channels > 2) {
496 av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
497 return AVERROR(EINVAL);
499 if (avctx->block_align < 1) {
500 av_log(avctx, AV_LOG_ERROR, "invalid block align\n");
501 return AVERROR(EINVAL);
504 if (avctx->bits_per_coded_sample == 16)
505 avctx->sample_fmt = AV_SAMPLE_FMT_S16;
507 avctx->sample_fmt = AV_SAMPLE_FMT_U8;
508 s->out_bps = av_get_bytes_per_sample(avctx->sample_fmt);
510 s->chunk_size = avctx->block_align + avctx->channels * (s->out_bps == 2);
512 avcodec_get_frame_defaults(&s->frame);
513 avctx->coded_frame = &s->frame;
515 av_log(avctx, AV_LOG_DEBUG, "%d channels, %d bits/sample, "
516 "block align = %d, sample rate = %d\n",
517 avctx->channels, avctx->bits_per_coded_sample, avctx->block_align,
523 static void decode_audio_s16(int16_t *out, const uint8_t *buf, int buf_size,
527 const uint8_t *buf_end = buf + buf_size;
529 int st = channels - 1;
531 /* decode initial raw sample */
532 for (ch = 0; ch < channels; ch++) {
533 predictor[ch] = (int16_t)AV_RL16(buf);
535 *out++ = predictor[ch];
538 /* decode DPCM samples */
540 while (buf < buf_end) {
543 predictor[ch] -= vmdaudio_table[b & 0x7F];
545 predictor[ch] += vmdaudio_table[b];
546 predictor[ch] = av_clip_int16(predictor[ch]);
547 *out++ = predictor[ch];
552 static int vmdaudio_decode_frame(AVCodecContext *avctx, void *data,
553 int *got_frame_ptr, AVPacket *avpkt)
555 const uint8_t *buf = avpkt->data;
556 const uint8_t *buf_end;
557 int buf_size = avpkt->size;
558 VmdAudioContext *s = avctx->priv_data;
559 int block_type, silent_chunks, audio_chunks;
561 uint8_t *output_samples_u8;
562 int16_t *output_samples_s16;
565 av_log(avctx, AV_LOG_WARNING, "skipping small junk packet\n");
571 if (block_type < BLOCK_TYPE_AUDIO || block_type > BLOCK_TYPE_SILENCE) {
572 av_log(avctx, AV_LOG_ERROR, "unknown block type: %d\n", block_type);
573 return AVERROR(EINVAL);
578 /* get number of silent chunks */
580 if (block_type == BLOCK_TYPE_INITIAL) {
583 av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
584 return AVERROR(EINVAL);
586 flags = AV_RB32(buf);
587 silent_chunks = av_popcount(flags);
590 } else if (block_type == BLOCK_TYPE_SILENCE) {
592 buf_size = 0; // should already be zero but set it just to be sure
595 /* ensure output buffer is large enough */
596 audio_chunks = buf_size / s->chunk_size;
598 /* get output buffer */
599 s->frame.nb_samples = ((silent_chunks + audio_chunks) * avctx->block_align) / avctx->channels;
600 if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
601 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
604 output_samples_u8 = s->frame.data[0];
605 output_samples_s16 = (int16_t *)s->frame.data[0];
607 /* decode silent chunks */
608 if (silent_chunks > 0) {
609 int silent_size = avctx->block_align * silent_chunks;
610 if (s->out_bps == 2) {
611 memset(output_samples_s16, 0x00, silent_size * 2);
612 output_samples_s16 += silent_size;
614 memset(output_samples_u8, 0x80, silent_size);
615 output_samples_u8 += silent_size;
619 /* decode audio chunks */
620 if (audio_chunks > 0) {
621 buf_end = buf + buf_size;
622 while ( buf_end - buf >= s->chunk_size) {
623 if (s->out_bps == 2) {
624 decode_audio_s16(output_samples_s16, buf, s->chunk_size,
626 output_samples_s16 += avctx->block_align;
628 memcpy(output_samples_u8, buf, s->chunk_size);
629 output_samples_u8 += avctx->block_align;
631 buf += s->chunk_size;
636 *(AVFrame *)data = s->frame;
643 * Public Data Structures
646 AVCodec ff_vmdvideo_decoder = {
648 .type = AVMEDIA_TYPE_VIDEO,
649 .id = AV_CODEC_ID_VMDVIDEO,
650 .priv_data_size = sizeof(VmdVideoContext),
651 .init = vmdvideo_decode_init,
652 .close = vmdvideo_decode_end,
653 .decode = vmdvideo_decode_frame,
654 .capabilities = CODEC_CAP_DR1,
655 .long_name = NULL_IF_CONFIG_SMALL("Sierra VMD video"),
658 AVCodec ff_vmdaudio_decoder = {
660 .type = AVMEDIA_TYPE_AUDIO,
661 .id = AV_CODEC_ID_VMDAUDIO,
662 .priv_data_size = sizeof(VmdAudioContext),
663 .init = vmdaudio_decode_init,
664 .decode = vmdaudio_decode_frame,
665 .capabilities = CODEC_CAP_DR1,
666 .long_name = NULL_IF_CONFIG_SMALL("Sierra VMD audio"),