libavcodec/vmdvideo.c

   1 /*
   2  * Sierra VMD video decoder
   3  *
   4  * This file is part of Libav.
   5  *
   6  * Libav is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * Libav is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with Libav; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 /**
  22  * @file
  23  * Sierra VMD video decoder
  24  * by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
  25  * for more information on the Sierra VMD format, visit:
  26  *   http://www.pcisys.net/~melanson/codecs/
  27  *
  28  * The video decoder outputs PAL8 colorspace data. The decoder expects
  29  * a 0x330-byte VMD file header to be transmitted via extradata during
  30  * codec initialization. Each encoded frame that is sent to this decoder
  31  * is expected to be prepended with the appropriate 16-byte frame
  32  * information record from the VMD file.
  33  */
  34
  35 #include <string.h>
  36
  37 #include "libavutil/common.h"
  38 #include "libavutil/intreadwrite.h"
  39
  40 #include "avcodec.h"
  41 #include "internal.h"
  42 #include "bytestream.h"
  43
  44 #define VMD_HEADER_SIZE 0x330
  45 #define PALETTE_COUNT 256
  46
  47 typedef struct VmdVideoContext {
  48
  49     AVCodecContext *avctx;
  50     AVFrame *prev_frame;
  51
  52     const unsigned char *buf;
  53     int size;
  54
  55     unsigned char palette[PALETTE_COUNT * 4];
  56     unsigned char *unpack_buffer;
  57     int unpack_buffer_size;
  58
  59     int x_off, y_off;
  60 } VmdVideoContext;
  61
  62 #define QUEUE_SIZE 0x1000
  63 #define QUEUE_MASK 0x0FFF
  64
  65 static void lz_unpack(const unsigned char *src, int src_len,
  66                       unsigned char *dest, int dest_len)
  67 {
  68     unsigned char *d;
  69     unsigned char *d_end;
  70     unsigned char queue[QUEUE_SIZE];
  71     unsigned int qpos;
  72     unsigned int dataleft;
  73     unsigned int chainofs;
  74     unsigned int chainlen;
  75     unsigned int speclen;
  76     unsigned char tag;
  77     unsigned int i, j;
  78     GetByteContext gb;
  79
  80     bytestream2_init(&gb, src, src_len);
  81     d = dest;
  82     d_end = d + dest_len;
  83     dataleft = bytestream2_get_le32(&gb);
  84     memset(queue, 0x20, QUEUE_SIZE);
  85     if (bytestream2_get_bytes_left(&gb) < 4)
  86         return;
  87     if (bytestream2_peek_le32(&gb) == 0x56781234) {
  88         bytestream2_get_le32(&gb);
  89         qpos = 0x111;
  90         speclen = 0xF + 3;
  91     } else {
  92         qpos = 0xFEE;
  93         speclen = 100;  /* no speclen */
  94     }
  95
  96     while (dataleft > 0 && bytestream2_get_bytes_left(&gb) > 0) {
  97         tag = bytestream2_get_byteu(&gb);
  98         if ((tag == 0xFF) && (dataleft > 8)) {
  99             if (d + 8 > d_end || bytestream2_get_bytes_left(&gb) < 8)
 100                 return;
 101             for (i = 0; i < 8; i++) {
 102                 queue[qpos++] = *d++ = bytestream2_get_byteu(&gb);
 103                 qpos &= QUEUE_MASK;
 104             }
 105             dataleft -= 8;
 106         } else {
 107             for (i = 0; i < 8; i++) {
 108                 if (dataleft == 0)
 109                     break;
 110                 if (tag & 0x01) {
 111                     if (d + 1 > d_end || bytestream2_get_bytes_left(&gb) < 1)
 112                         return;
 113                     queue[qpos++] = *d++ = bytestream2_get_byte(&gb);
 114                     qpos &= QUEUE_MASK;
 115                     dataleft--;
 116                 } else {
 117                     chainofs = bytestream2_get_byte(&gb);
 118                     chainofs |= ((bytestream2_peek_byte(&gb) & 0xF0) << 4);
 119                     chainlen = (bytestream2_get_byte(&gb) & 0x0F) + 3;
 120                     if (chainlen == speclen) {
 121                         chainlen = bytestream2_get_byte(&gb) + 0xF + 3;
 122                     }
 123                     if (d + chainlen > d_end)
 124                         return;
 125                     for (j = 0; j < chainlen; j++) {
 126                         *d = queue[chainofs++ & QUEUE_MASK];
 127                         queue[qpos++] = *d++;
 128                         qpos &= QUEUE_MASK;
 129                     }
 130                     dataleft -= chainlen;
 131                 }
 132                 tag >>= 1;
 133             }
 134         }
 135     }
 136 }
 137
 138 static int rle_unpack(const unsigned char *src, unsigned char *dest,
 139     int src_count, int src_size, int dest_len)
 140 {
 141     unsigned char *pd;
 142     int i, l, used = 0;
 143     unsigned char *dest_end = dest + dest_len;
 144     GetByteContext gb;
 145     uint16_t run_val;
 146
 147     bytestream2_init(&gb, src, src_size);
 148     pd = dest;
 149     if (src_count & 1) {
 150         if (bytestream2_get_bytes_left(&gb) < 1)
 151             return 0;
 152         *pd++ = bytestream2_get_byteu(&gb);
 153         used++;
 154     }
 155
 156     do {
 157         if (bytestream2_get_bytes_left(&gb) < 1)
 158             break;
 159         l = bytestream2_get_byteu(&gb);
 160         if (l & 0x80) {
 161             l = (l & 0x7F) * 2;
 162             if (pd + l > dest_end || bytestream2_get_bytes_left(&gb) < l)
 163                 return bytestream2_tell(&gb);
 164             bytestream2_get_buffer(&gb, pd, l);
 165             pd += l;
 166         } else {
 167             if (pd + l > dest_end || bytestream2_get_bytes_left(&gb) < 2)
 168                 return bytestream2_tell(&gb);
 169             run_val = bytestream2_get_ne16(&gb);
 170             for (i = 0; i < l; i++) {
 171                 AV_WN16(pd, run_val);
 172                 pd += 2;
 173             }
 174             l *= 2;
 175         }
 176         used += l;
 177     } while (used < src_count);
 178
 179     return bytestream2_tell(&gb);
 180 }
 181
 182 static int vmd_decode(VmdVideoContext *s, AVFrame *frame)
 183 {
 184     int i;
 185     unsigned int *palette32;
 186     unsigned char r, g, b;
 187
 188     GetByteContext gb;
 189
 190     unsigned char meth;
 191     unsigned char *dp;   /* pointer to current frame */
 192     unsigned char *pp;   /* pointer to previous frame */
 193     unsigned char len;
 194     int ofs;
 195
 196     int frame_x, frame_y;
 197     int frame_width, frame_height;
 198
 199     frame_x = AV_RL16(&s->buf[6]);
 200     frame_y = AV_RL16(&s->buf[8]);
 201     frame_width = AV_RL16(&s->buf[10]) - frame_x + 1;
 202     frame_height = AV_RL16(&s->buf[12]) - frame_y + 1;
 203     if (frame_x < 0 || frame_width < 0 ||
 204         frame_x >= s->avctx->width ||
 205         frame_width > s->avctx->width ||
 206         frame_x + frame_width > s->avctx->width) {
 207         av_log(s->avctx, AV_LOG_ERROR,
 208                "Invalid horizontal range %d-%d\n",
 209                frame_x, frame_width);
 210         return AVERROR_INVALIDDATA;
 211     }
 212     if (frame_y < 0 || frame_height < 0 ||
 213         frame_y >= s->avctx->height ||
 214         frame_height > s->avctx->height ||
 215         frame_y + frame_height > s->avctx->height) {
 216         av_log(s->avctx, AV_LOG_ERROR,
 217                "Invalid vertical range %d-%d\n",
 218                frame_x, frame_width);
 219         return AVERROR_INVALIDDATA;
 220     }
 221
 222     if ((frame_width == s->avctx->width && frame_height == s->avctx->height) &&
 223         (frame_x || frame_y)) {
 224
 225         s->x_off = frame_x;
 226         s->y_off = frame_y;
 227     }
 228     frame_x -= s->x_off;
 229     frame_y -= s->y_off;
 230
 231     /* if only a certain region will be updated, copy the entire previous
 232      * frame before the decode */
 233     if (s->prev_frame->data[0] &&
 234         (frame_x || frame_y || (frame_width != s->avctx->width) ||
 235         (frame_height != s->avctx->height))) {
 236
 237         memcpy(frame->data[0], s->prev_frame->data[0],
 238             s->avctx->height * frame->linesize[0]);
 239     }
 240
 241     /* check if there is a new palette */
 242     bytestream2_init(&gb, s->buf + 16, s->size - 16);
 243     if (s->buf[15] & 0x02) {
 244         bytestream2_skip(&gb, 2);
 245         palette32 = (unsigned int *)s->palette;
 246         if (bytestream2_get_bytes_left(&gb) >= PALETTE_COUNT * 3) {
 247             for (i = 0; i < PALETTE_COUNT; i++) {
 248                 r = bytestream2_get_byteu(&gb) * 4;
 249                 g = bytestream2_get_byteu(&gb) * 4;
 250                 b = bytestream2_get_byteu(&gb) * 4;
 251                 palette32[i] = (r << 16) | (g << 8) | (b);
 252             }
 253         } else {
 254             av_log(s->avctx, AV_LOG_ERROR, "Incomplete palette\n");
 255             return AVERROR_INVALIDDATA;
 256         }
 257         s->size -= PALETTE_COUNT * 3 + 2;
 258     }
 259
 260     if (!s->size)
 261         return 0;
 262
 263     /* originally UnpackFrame in VAG's code */
 264     if (bytestream2_get_bytes_left(&gb) < 1)
 265         return AVERROR_INVALIDDATA;
 266     meth = bytestream2_get_byteu(&gb);
 267     if (meth & 0x80) {
 268         if (!s->unpack_buffer_size) {
 269             av_log(s->avctx, AV_LOG_ERROR,
 270                    "Trying to unpack LZ-compressed frame with no LZ buffer\n");
 271             return AVERROR_INVALIDDATA;
 272         }
 273         lz_unpack(gb.buffer, bytestream2_get_bytes_left(&gb),
 274                   s->unpack_buffer, s->unpack_buffer_size);
 275         meth &= 0x7F;
 276         bytestream2_init(&gb, s->unpack_buffer, s->unpack_buffer_size);
 277     }
 278
 279     dp = &frame->data[0][frame_y * frame->linesize[0] + frame_x];
 280     pp = &s->prev_frame->data[0][frame_y * s->prev_frame->linesize[0] + frame_x];
 281     switch (meth) {
 282     case 1:
 283         for (i = 0; i < frame_height; i++) {
 284             ofs = 0;
 285             do {
 286                 len = bytestream2_get_byte(&gb);
 287                 if (len & 0x80) {
 288                     len = (len & 0x7F) + 1;
 289                     if (ofs + len > frame_width ||
 290                         bytestream2_get_bytes_left(&gb) < len)
 291                         return AVERROR_INVALIDDATA;
 292                     bytestream2_get_buffer(&gb, &dp[ofs], len);
 293                     ofs += len;
 294                 } else {
 295                     /* interframe pixel copy */
 296                     if (ofs + len + 1 > frame_width || !s->prev_frame->data[0])
 297                         return AVERROR_INVALIDDATA;
 298                     memcpy(&dp[ofs], &pp[ofs], len + 1);
 299                     ofs += len + 1;
 300                 }
 301             } while (ofs < frame_width);
 302             if (ofs > frame_width) {
 303                 av_log(s->avctx, AV_LOG_ERROR,
 304                        "VMD video: offset > width (%d > %d)\n",
 305                        ofs, frame_width);
 306                 return AVERROR_INVALIDDATA;
 307             }
 308             dp += frame->linesize[0];
 309             pp += s->prev_frame->linesize[0];
 310         }
 311         break;
 312
 313     case 2:
 314         for (i = 0; i < frame_height; i++) {
 315             bytestream2_get_buffer(&gb, dp, frame_width);
 316             dp += frame->linesize[0];
 317             pp += s->prev_frame->linesize[0];
 318         }
 319         break;
 320
 321     case 3:
 322         for (i = 0; i < frame_height; i++) {
 323             ofs = 0;
 324             do {
 325                 len = bytestream2_get_byte(&gb);
 326                 if (len & 0x80) {
 327                     len = (len & 0x7F) + 1;
 328                     if (bytestream2_peek_byte(&gb) == 0xFF) {
 329                         int slen = len;
 330                         bytestream2_get_byte(&gb);
 331                         len = rle_unpack(gb.buffer, &dp[ofs],
 332                                          len, bytestream2_get_bytes_left(&gb),
 333                                          frame_width - ofs);
 334                         ofs += slen;
 335                         bytestream2_skip(&gb, len);
 336                     } else {
 337                         bytestream2_get_buffer(&gb, &dp[ofs], len);
 338                         ofs += len;
 339                     }
 340                 } else {
 341                     /* interframe pixel copy */
 342                     if (ofs + len + 1 > frame_width || !s->prev_frame->data[0])
 343                         return AVERROR_INVALIDDATA;
 344                     memcpy(&dp[ofs], &pp[ofs], len + 1);
 345                     ofs += len + 1;
 346                 }
 347             } while (ofs < frame_width);
 348             if (ofs > frame_width) {
 349                 av_log(s->avctx, AV_LOG_ERROR,
 350                        "VMD video: offset > width (%d > %d)\n",
 351                        ofs, frame_width);
 352                 return AVERROR_INVALIDDATA;
 353             }
 354             dp += frame->linesize[0];
 355             pp += s->prev_frame->linesize[0];
 356         }
 357         break;
 358     }
 359     return 0;
 360 }
 361
 362 static av_cold int vmdvideo_decode_end(AVCodecContext *avctx)
 363 {
 364     VmdVideoContext *s = avctx->priv_data;
 365
 366     av_frame_free(&s->prev_frame);
 367     av_free(s->unpack_buffer);
 368
 369     return 0;
 370 }
 371
 372 static av_cold int vmdvideo_decode_init(AVCodecContext *avctx)
 373 {
 374     VmdVideoContext *s = avctx->priv_data;
 375     int i;
 376     unsigned int *palette32;
 377     int palette_index = 0;
 378     unsigned char r, g, b;
 379     unsigned char *vmd_header;
 380     unsigned char *raw_palette;
 381
 382     s->avctx = avctx;
 383     avctx->pix_fmt = AV_PIX_FMT_PAL8;
 384
 385     /* make sure the VMD header made it */
 386     if (s->avctx->extradata_size != VMD_HEADER_SIZE) {
 387         av_log(s->avctx, AV_LOG_ERROR, "VMD video: expected extradata size of %d\n",
 388             VMD_HEADER_SIZE);
 389         return -1;
 390     }
 391     vmd_header = (unsigned char *)avctx->extradata;
 392
 393     s->unpack_buffer_size = AV_RL32(&vmd_header[800]);
 394     if (s->unpack_buffer_size) {
 395         s->unpack_buffer = av_malloc(s->unpack_buffer_size);
 396         if (!s->unpack_buffer)
 397             return AVERROR(ENOMEM);
 398     }
 399
 400     /* load up the initial palette */
 401     raw_palette = &vmd_header[28];
 402     palette32 = (unsigned int *)s->palette;
 403     for (i = 0; i < PALETTE_COUNT; i++) {
 404         r = raw_palette[palette_index++] * 4;
 405         g = raw_palette[palette_index++] * 4;
 406         b = raw_palette[palette_index++] * 4;
 407         palette32[i] = (r << 16) | (g << 8) | (b);
 408     }
 409
 410     s->prev_frame = av_frame_alloc();
 411     if (!s->prev_frame) {
 412         vmdvideo_decode_end(avctx);
 413         return AVERROR(ENOMEM);
 414     }
 415
 416     return 0;
 417 }
 418
 419 static int vmdvideo_decode_frame(AVCodecContext *avctx,
 420                                  void *data, int *got_frame,
 421                                  AVPacket *avpkt)
 422 {
 423     const uint8_t *buf = avpkt->data;
 424     int buf_size = avpkt->size;
 425     VmdVideoContext *s = avctx->priv_data;
 426     AVFrame *frame = data;
 427     int ret;
 428
 429     s->buf = buf;
 430     s->size = buf_size;
 431
 432     if (buf_size < 16)
 433         return AVERROR_INVALIDDATA;
 434
 435     if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) {
 436         av_log(s->avctx, AV_LOG_ERROR, "VMD Video: get_buffer() failed\n");
 437         return ret;
 438     }
 439
 440     if ((ret = vmd_decode(s, frame)) < 0)
 441         return ret;
 442
 443     /* make the palette available on the way out */
 444     memcpy(frame->data[1], s->palette, PALETTE_COUNT * 4);
 445
 446     /* shuffle frames */
 447     av_frame_unref(s->prev_frame);
 448     if ((ret = av_frame_ref(s->prev_frame, frame)) < 0)
 449         return ret;
 450
 451     *got_frame      = 1;
 452
 453     /* report that the buffer was completely consumed */
 454     return buf_size;
 455 }
 456
 457 AVCodec ff_vmdvideo_decoder = {
 458     .name           = "vmdvideo",
 459     .long_name      = NULL_IF_CONFIG_SMALL("Sierra VMD video"),
 460     .type           = AVMEDIA_TYPE_VIDEO,
 461     .id             = AV_CODEC_ID_VMDVIDEO,
 462     .priv_data_size = sizeof(VmdVideoContext),
 463     .init           = vmdvideo_decode_init,
 464     .close          = vmdvideo_decode_end,
 465     .decode         = vmdvideo_decode_frame,
 466     .capabilities   = AV_CODEC_CAP_DR1,
 467 };