ffmpeg/libavcodec/vmdvideo.c

   1 /*
   2  * Sierra VMD video decoder
   3  * Copyright (c) 2004 The FFmpeg Project
   4  *
   5  * This file is part of FFmpeg.
   6  *
   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.
  11  *
  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.
  16  *
  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
  20  */
  21
  22 /**
  23  * @file
  24  * Sierra VMD video decoder
  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/
  28  *
  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.
  34  */
  35
  36 #include <string.h>
  37
  38 #include "libavutil/common.h"
  39 #include "libavutil/intreadwrite.h"
  40
  41 #include "avcodec.h"
  42 #include "internal.h"
  43 #include "bytestream.h"
  44
  45 #define VMD_HEADER_SIZE 0x330
  46 #define PALETTE_COUNT 256
  47
  48 typedef struct VmdVideoContext {
  49
  50     AVCodecContext *avctx;
  51     AVFrame *prev_frame;
  52
  53     const unsigned char *buf;
  54     int size;
  55
  56     unsigned char palette[PALETTE_COUNT * 4];
  57     unsigned char *unpack_buffer;
  58     int unpack_buffer_size;
  59
  60     int x_off, y_off;
  61 } VmdVideoContext;
  62
  63 #define QUEUE_SIZE 0x1000
  64 #define QUEUE_MASK 0x0FFF
  65
  66 static int lz_unpack(const unsigned char *src, int src_len,
  67                       unsigned char *dest, int dest_len)
  68 {
  69     unsigned char *d;
  70     unsigned char *d_end;
  71     unsigned char queue[QUEUE_SIZE];
  72     unsigned int qpos;
  73     unsigned int dataleft;
  74     unsigned int chainofs;
  75     unsigned int chainlen;
  76     unsigned int speclen;
  77     unsigned char tag;
  78     unsigned int i, j;
  79     GetByteContext gb;
  80
  81     bytestream2_init(&gb, src, src_len);
  82     d = dest;
  83     d_end = d + dest_len;
  84     dataleft = bytestream2_get_le32(&gb);
  85     memset(queue, 0x20, QUEUE_SIZE);
  86     if (bytestream2_get_bytes_left(&gb) < 4)
  87         return AVERROR_INVALIDDATA;
  88     if (bytestream2_peek_le32(&gb) == 0x56781234) {
  89         bytestream2_skipu(&gb, 4);
  90         qpos = 0x111;
  91         speclen = 0xF + 3;
  92     } else {
  93         qpos = 0xFEE;
  94         speclen = 100;  /* no speclen */
  95     }
  96
  97     while (dataleft > 0 && bytestream2_get_bytes_left(&gb) > 0) {
  98         tag = bytestream2_get_byteu(&gb);
  99         if ((tag == 0xFF) && (dataleft > 8)) {
 100             if (d_end - d < 8 || bytestream2_get_bytes_left(&gb) < 8)
 101                 return AVERROR_INVALIDDATA;
 102             for (i = 0; i < 8; i++) {
 103                 queue[qpos++] = *d++ = bytestream2_get_byteu(&gb);
 104                 qpos &= QUEUE_MASK;
 105             }
 106             dataleft -= 8;
 107         } else {
 108             for (i = 0; i < 8; i++) {
 109                 if (dataleft == 0)
 110                     break;
 111                 if (tag & 0x01) {
 112                     if (d_end - d < 1 || bytestream2_get_bytes_left(&gb) < 1)
 113                         return AVERROR_INVALIDDATA;
 114                     queue[qpos++] = *d++ = bytestream2_get_byteu(&gb);
 115                     qpos &= QUEUE_MASK;
 116                     dataleft--;
 117                 } else {
 118                     chainofs = bytestream2_get_byte(&gb);
 119                     chainofs |= ((bytestream2_peek_byte(&gb) & 0xF0) << 4);
 120                     chainlen = (bytestream2_get_byte(&gb) & 0x0F) + 3;
 121                     if (chainlen == speclen) {
 122                         chainlen = bytestream2_get_byte(&gb) + 0xF + 3;
 123                     }
 124                     if (d_end - d < chainlen)
 125                         return AVERROR_INVALIDDATA;
 126                     for (j = 0; j < chainlen; j++) {
 127                         *d = queue[chainofs++ & QUEUE_MASK];
 128                         queue[qpos++] = *d++;
 129                         qpos &= QUEUE_MASK;
 130                     }
 131                     dataleft -= chainlen;
 132                 }
 133                 tag >>= 1;
 134             }
 135         }
 136     }
 137     return d - dest;
 138 }
 139 static int rle_unpack(const unsigned char *src, unsigned char *dest,
 140                       int src_count, int src_size, int dest_len)
 141 {
 142     unsigned char *pd;
 143     int i, l, used = 0;
 144     unsigned char *dest_end = dest + dest_len;
 145     GetByteContext gb;
 146     uint16_t run_val;
 147
 148     bytestream2_init(&gb, src, src_size);
 149     pd = dest;
 150     if (src_count & 1) {
 151         if (bytestream2_get_bytes_left(&gb) < 1)
 152             return 0;
 153         *pd++ = bytestream2_get_byteu(&gb);
 154         used++;
 155     }
 156
 157     do {
 158         if (bytestream2_get_bytes_left(&gb) < 1)
 159             break;
 160         l = bytestream2_get_byteu(&gb);
 161         if (l & 0x80) {
 162             l = (l & 0x7F) * 2;
 163             if (dest_end - pd < l || bytestream2_get_bytes_left(&gb) < l)
 164                 return bytestream2_tell(&gb);
 165             bytestream2_get_bufferu(&gb, pd, l);
 166             pd += l;
 167         } else {
 168             if (dest_end - pd < 2*l || bytestream2_get_bytes_left(&gb) < 2)
 169                 return bytestream2_tell(&gb);
 170             run_val = bytestream2_get_ne16(&gb);
 171             for (i = 0; i < l; i++) {
 172                 AV_WN16(pd, run_val);
 173                 pd += 2;
 174             }
 175             l *= 2;
 176         }
 177         used += l;
 178     } while (used < src_count);
 179
 180     return bytestream2_tell(&gb);
 181 }
 182
 183 static int vmd_decode(VmdVideoContext *s, AVFrame *frame)
 184 {
 185     int i;
 186     unsigned int *palette32;
 187     unsigned char r, g, b;
 188
 189     GetByteContext gb;
 190
 191     unsigned char meth;
 192     unsigned char *dp;   /* pointer to current frame */
 193     unsigned char *pp;   /* pointer to previous frame */
 194     unsigned char len;
 195     int ofs;
 196
 197     int frame_x, frame_y;
 198     int frame_width, frame_height;
 199
 200     frame_x = AV_RL16(&s->buf[6]);
 201     frame_y = AV_RL16(&s->buf[8]);
 202     frame_width = AV_RL16(&s->buf[10]) - frame_x + 1;
 203     frame_height = AV_RL16(&s->buf[12]) - frame_y + 1;
 204
 205     if ((frame_width == s->avctx->width && frame_height == s->avctx->height) &&
 206         (frame_x || frame_y)) {
 207
 208         s->x_off = frame_x;
 209         s->y_off = frame_y;
 210     }
 211     frame_x -= s->x_off;
 212     frame_y -= s->y_off;
 213
 214     if (frame_x < 0 || frame_width < 0 ||
 215         frame_x >= s->avctx->width ||
 216         frame_width > s->avctx->width ||
 217         frame_x + frame_width > s->avctx->width) {
 218         av_log(s->avctx, AV_LOG_ERROR,
 219                "Invalid horizontal range %d-%d\n",
 220                frame_x, frame_width);
 221         return AVERROR_INVALIDDATA;
 222     }
 223     if (frame_y < 0 || frame_height < 0 ||
 224         frame_y >= s->avctx->height ||
 225         frame_height > s->avctx->height ||
 226         frame_y + frame_height > s->avctx->height) {
 227         av_log(s->avctx, AV_LOG_ERROR,
 228                "Invalid vertical range %d-%d\n",
 229                frame_x, frame_width);
 230         return AVERROR_INVALIDDATA;
 231     }
 232
 233     /* if only a certain region will be updated, copy the entire previous
 234      * frame before the decode */
 235     if (s->prev_frame->data[0] &&
 236         (frame_x || frame_y || (frame_width != s->avctx->width) ||
 237         (frame_height != s->avctx->height))) {
 238
 239         memcpy(frame->data[0], s->prev_frame->data[0],
 240             s->avctx->height * frame->linesize[0]);
 241     }
 242
 243     /* check if there is a new palette */
 244     bytestream2_init(&gb, s->buf + 16, s->size - 16);
 245     if (s->buf[15] & 0x02) {
 246         bytestream2_skip(&gb, 2);
 247         palette32 = (unsigned int *)s->palette;
 248         if (bytestream2_get_bytes_left(&gb) >= PALETTE_COUNT * 3) {
 249             for (i = 0; i < PALETTE_COUNT; i++) {
 250                 r = bytestream2_get_byteu(&gb) * 4;
 251                 g = bytestream2_get_byteu(&gb) * 4;
 252                 b = bytestream2_get_byteu(&gb) * 4;
 253                 palette32[i] = 0xFFU << 24 | (r << 16) | (g << 8) | (b);
 254                 palette32[i] |= palette32[i] >> 6 & 0x30303;
 255             }
 256         } else {
 257             av_log(s->avctx, AV_LOG_ERROR, "Incomplete palette\n");
 258             return AVERROR_INVALIDDATA;
 259         }
 260     }
 261
 262     if (!s->size)
 263         return 0;
 264
 265     /* originally UnpackFrame in VAG's code */
 266     if (bytestream2_get_bytes_left(&gb) < 1)
 267         return AVERROR_INVALIDDATA;
 268     meth = bytestream2_get_byteu(&gb);
 269     if (meth & 0x80) {
 270         int size;
 271         if (!s->unpack_buffer_size) {
 272             av_log(s->avctx, AV_LOG_ERROR,
 273                    "Trying to unpack LZ-compressed frame with no LZ buffer\n");
 274             return AVERROR_INVALIDDATA;
 275         }
 276         size = lz_unpack(gb.buffer, bytestream2_get_bytes_left(&gb),
 277                          s->unpack_buffer, s->unpack_buffer_size);
 278         if (size < 0)
 279             return size;
 280         meth &= 0x7F;
 281         bytestream2_init(&gb, s->unpack_buffer, size);
 282     }
 283
 284     dp = &frame->data[0][frame_y * frame->linesize[0] + frame_x];
 285     pp = &s->prev_frame->data[0][frame_y * s->prev_frame->linesize[0] + frame_x];
 286     switch (meth) {
 287     case 1:
 288         for (i = 0; i < frame_height; i++) {
 289             ofs = 0;
 290             do {
 291                 len = bytestream2_get_byte(&gb);
 292                 if (len & 0x80) {
 293                     len = (len & 0x7F) + 1;
 294                     if (ofs + len > frame_width ||
 295                         bytestream2_get_bytes_left(&gb) < len)
 296                         return AVERROR_INVALIDDATA;
 297                     bytestream2_get_bufferu(&gb, &dp[ofs], len);
 298                     ofs += len;
 299                 } else {
 300                     /* interframe pixel copy */
 301                     if (ofs + len + 1 > frame_width || !s->prev_frame->data[0])
 302                         return AVERROR_INVALIDDATA;
 303                     memcpy(&dp[ofs], &pp[ofs], len + 1);
 304                     ofs += len + 1;
 305                 }
 306             } while (ofs < frame_width);
 307             if (ofs > frame_width) {
 308                 av_log(s->avctx, AV_LOG_ERROR,
 309                        "offset > width (%d > %d)\n",
 310                        ofs, frame_width);
 311                 return AVERROR_INVALIDDATA;
 312             }
 313             dp += frame->linesize[0];
 314             pp += s->prev_frame->linesize[0];
 315         }
 316         break;
 317
 318     case 2:
 319         for (i = 0; i < frame_height; i++) {
 320             bytestream2_get_buffer(&gb, dp, frame_width);
 321             dp += frame->linesize[0];
 322             pp += s->prev_frame->linesize[0];
 323         }
 324         break;
 325
 326     case 3:
 327         for (i = 0; i < frame_height; i++) {
 328             ofs = 0;
 329             do {
 330                 len = bytestream2_get_byte(&gb);
 331                 if (len & 0x80) {
 332                     len = (len & 0x7F) + 1;
 333                     if (bytestream2_peek_byte(&gb) == 0xFF) {
 334                         int slen = len;
 335                         bytestream2_get_byte(&gb);
 336                         len = rle_unpack(gb.buffer, &dp[ofs],
 337                                          len, bytestream2_get_bytes_left(&gb),
 338                                          frame_width - ofs);
 339                         ofs += slen;
 340                         bytestream2_skip(&gb, len);
 341                     } else {
 342                         if (ofs + len > frame_width ||
 343                             bytestream2_get_bytes_left(&gb) < len)
 344                             return AVERROR_INVALIDDATA;
 345                         bytestream2_get_buffer(&gb, &dp[ofs], len);
 346                         ofs += len;
 347                     }
 348                 } else {
 349                     /* interframe pixel copy */
 350                     if (ofs + len + 1 > frame_width || !s->prev_frame->data[0])
 351                         return AVERROR_INVALIDDATA;
 352                     memcpy(&dp[ofs], &pp[ofs], len + 1);
 353                     ofs += len + 1;
 354                 }
 355             } while (ofs < frame_width);
 356             if (ofs > frame_width) {
 357                 av_log(s->avctx, AV_LOG_ERROR,
 358                        "offset > width (%d > %d)\n",
 359                        ofs, frame_width);
 360                 return AVERROR_INVALIDDATA;
 361             }
 362             dp += frame->linesize[0];
 363             pp += s->prev_frame->linesize[0];
 364         }
 365         break;
 366     }
 367     return 0;
 368 }
 369
 370 static av_cold int vmdvideo_decode_end(AVCodecContext *avctx)
 371 {
 372     VmdVideoContext *s = avctx->priv_data;
 373
 374     av_frame_free(&s->prev_frame);
 375     av_freep(&s->unpack_buffer);
 376     s->unpack_buffer_size = 0;
 377
 378     return 0;
 379 }
 380
 381 static av_cold int vmdvideo_decode_init(AVCodecContext *avctx)
 382 {
 383     VmdVideoContext *s = avctx->priv_data;
 384     int i;
 385     unsigned int *palette32;
 386     int palette_index = 0;
 387     unsigned char r, g, b;
 388     unsigned char *vmd_header;
 389     unsigned char *raw_palette;
 390
 391     s->avctx = avctx;
 392     avctx->pix_fmt = AV_PIX_FMT_PAL8;
 393
 394     /* make sure the VMD header made it */
 395     if (s->avctx->extradata_size != VMD_HEADER_SIZE) {
 396         av_log(s->avctx, AV_LOG_ERROR, "expected extradata size of %d\n",
 397             VMD_HEADER_SIZE);
 398         return AVERROR_INVALIDDATA;
 399     }
 400     vmd_header = (unsigned char *)avctx->extradata;
 401
 402     s->unpack_buffer_size = AV_RL32(&vmd_header[800]);
 403     if (s->unpack_buffer_size) {
 404         s->unpack_buffer = av_malloc(s->unpack_buffer_size);
 405         if (!s->unpack_buffer)
 406             return AVERROR(ENOMEM);
 407     }
 408
 409     /* load up the initial palette */
 410     raw_palette = &vmd_header[28];
 411     palette32 = (unsigned int *)s->palette;
 412     for (i = 0; i < PALETTE_COUNT; i++) {
 413         r = raw_palette[palette_index++] * 4;
 414         g = raw_palette[palette_index++] * 4;
 415         b = raw_palette[palette_index++] * 4;
 416         palette32[i] = 0xFFU << 24 | (r << 16) | (g << 8) | (b);
 417         palette32[i] |= palette32[i] >> 6 & 0x30303;
 418     }
 419
 420     s->prev_frame = av_frame_alloc();
 421     if (!s->prev_frame) {
 422         vmdvideo_decode_end(avctx);
 423         return AVERROR(ENOMEM);
 424     }
 425
 426     return 0;
 427 }
 428
 429 static int vmdvideo_decode_frame(AVCodecContext *avctx,
 430                                  void *data, int *got_frame,
 431                                  AVPacket *avpkt)
 432 {
 433     const uint8_t *buf = avpkt->data;
 434     int buf_size = avpkt->size;
 435     VmdVideoContext *s = avctx->priv_data;
 436     AVFrame *frame = data;
 437     int ret;
 438
 439     s->buf = buf;
 440     s->size = buf_size;
 441
 442     if (buf_size < 16)
 443         return AVERROR_INVALIDDATA;
 444
 445     if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
 446         return ret;
 447
 448     if ((ret = vmd_decode(s, frame)) < 0)
 449         return ret;
 450
 451     /* make the palette available on the way out */
 452     memcpy(frame->data[1], s->palette, PALETTE_COUNT * 4);
 453
 454     /* shuffle frames */
 455     av_frame_unref(s->prev_frame);
 456     if ((ret = av_frame_ref(s->prev_frame, frame)) < 0)
 457         return ret;
 458
 459     *got_frame      = 1;
 460
 461     /* report that the buffer was completely consumed */
 462     return buf_size;
 463 }
 464
 465 AVCodec ff_vmdvideo_decoder = {
 466     .name           = "vmdvideo",
 467     .long_name      = NULL_IF_CONFIG_SMALL("Sierra VMD video"),
 468     .type           = AVMEDIA_TYPE_VIDEO,
 469     .id             = AV_CODEC_ID_VMDVIDEO,
 470     .priv_data_size = sizeof(VmdVideoContext),
 471     .init           = vmdvideo_decode_init,
 472     .close          = vmdvideo_decode_end,
 473     .decode         = vmdvideo_decode_frame,
 474     .capabilities   = CODEC_CAP_DR1,
 475 };