quicktime/ffmpeg/libavcodec/tscc.c

   1 /*
   2  * TechSmith Camtasia decoder
   3  * Copyright (c) 2004 Konstantin Shishkov
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  *
  19  */
  20
  21 /**
  22  * @file tscc.c
  23  * TechSmith Camtasia decoder
  24  *
  25  * Fourcc: TSCC
  26  *
  27  * Codec is very simple:
  28  *  it codes picture (picture difference, really)
  29  *  with algorithm almost identical to Windows RLE8,
  30  *  only without padding and with greater pixel sizes,
  31  *  then this coded picture is packed with ZLib
  32  *
  33  * Supports: BGR8,BGR555,BGR24 - only BGR8 and BGR555 tested
  34  *
  35  */
  36
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39
  40 #include "common.h"
  41 #include "avcodec.h"
  42
  43 #ifdef CONFIG_ZLIB
  44 #include <zlib.h>
  45 #endif
  46
  47
  48 /*
  49  * Decoder context
  50  */
  51 typedef struct TsccContext {
  52
  53     AVCodecContext *avctx;
  54     AVFrame pic;
  55
  56     // Bits per pixel
  57     int bpp;
  58     // Decompressed data size
  59     unsigned int decomp_size;
  60     // Decompression buffer
  61     unsigned char* decomp_buf;
  62     int height;
  63 #ifdef CONFIG_ZLIB
  64     z_stream zstream;
  65 #endif
  66 } CamtasiaContext;
  67
  68 /*
  69  *
  70  * Decode RLE - almost identical to Windows BMP RLE8
  71  *              and enhanced to bigger color depths
  72  *
  73  */
  74
  75 static int decode_rle(CamtasiaContext *c, unsigned int srcsize)
  76 {
  77     unsigned char *src = c->decomp_buf;
  78     unsigned char *output, *output_end;
  79     int p1, p2, line=c->height, pos=0, i;
  80
  81     output = c->pic.data[0] + (c->height - 1) * c->pic.linesize[0];
  82     output_end = c->pic.data[0] + (c->height) * c->pic.linesize[0];
  83     while(src < c->decomp_buf + srcsize) {
  84         p1 = *src++;
  85         if(p1 == 0) { //Escape code
  86             p2 = *src++;
  87             if(p2 == 0) { //End-of-line
  88                 output = c->pic.data[0] + (--line) * c->pic.linesize[0];
  89                 if (line < 0)
  90                     return -1;
  91                 pos = 0;
  92                 continue;
  93             } else if(p2 == 1) { //End-of-picture
  94                 return 0;
  95             } else if(p2 == 2) { //Skip
  96                 p1 = *src++;
  97                 p2 = *src++;
  98                 line -= p2;
  99                 if (line < 0)
 100                     return -1;
 101                 pos += p1;
 102                 output = c->pic.data[0] + line * c->pic.linesize[0] + pos * (c->bpp / 8);
 103                 continue;
 104             }
 105             // Copy data
 106             if (output + p2 * (c->bpp / 8) > output_end) {
 107                 src += p2 * (c->bpp / 8);
 108                 continue;
 109             }
 110             for(i = 0; i < p2 * (c->bpp / 8); i++) {
 111                 *output++ = *src++;
 112             }
 113             // RLE8 copy is actually padded - and runs are not!
 114             if(c->bpp == 8 && (p2 & 1)) {
 115                 src++;
 116             }
 117             pos += p2;
 118         } else { //Run of pixels
 119             int pix[4]; //original pixel
 120             switch(c->bpp){
 121             case  8: pix[0] = *src++;
 122                      break;
 123             case 16: pix[0] = *src++;
 124                      pix[1] = *src++;
 125                      break;
 126             case 24: pix[0] = *src++;
 127                      pix[1] = *src++;
 128                      pix[2] = *src++;
 129                      break;
 130             case 32: pix[0] = *src++;
 131                      pix[1] = *src++;
 132                      pix[2] = *src++;
 133                      pix[3] = *src++;
 134                      break;
 135             }
 136             if (output + p1 * (c->bpp / 8) > output_end)
 137                 continue;
 138             for(i = 0; i < p1; i++) {
 139                 switch(c->bpp){
 140                 case  8: *output++ = pix[0];
 141                          break;
 142                 case 16: *output++ = pix[0];
 143                          *output++ = pix[1];
 144                          break;
 145                 case 24: *output++ = pix[0];
 146                          *output++ = pix[1];
 147                          *output++ = pix[2];
 148                          break;
 149                 case 32: *output++ = pix[0];
 150                          *output++ = pix[1];
 151                          *output++ = pix[2];
 152                          *output++ = pix[3];
 153                          break;
 154                 }
 155             }
 156             pos += p1;
 157         }
 158     }
 159
 160     av_log(c->avctx, AV_LOG_ERROR, "Camtasia warning: no End-of-picture code\n");
 161     return 1;
 162 }
 163
 164 /*
 165  *
 166  * Decode a frame
 167  *
 168  */
 169 static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8_t *buf, int buf_size)
 170 {
 171     CamtasiaContext * const c = (CamtasiaContext *)avctx->priv_data;
 172     unsigned char *encoded = (unsigned char *)buf;
 173     unsigned char *outptr;
 174 #ifdef CONFIG_ZLIB
 175     int zret; // Zlib return code
 176 #endif
 177     int len = buf_size;
 178
 179     if(c->pic.data[0])
 180             avctx->release_buffer(avctx, &c->pic);
 181
 182     c->pic.reference = 1;
 183     c->pic.buffer_hints = FF_BUFFER_HINTS_VALID;
 184     if(avctx->get_buffer(avctx, &c->pic) < 0){
 185         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 186         return -1;
 187     }
 188
 189     outptr = c->pic.data[0]; // Output image pointer
 190
 191 #ifdef CONFIG_ZLIB
 192     zret = inflateReset(&(c->zstream));
 193     if (zret != Z_OK) {
 194         av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
 195         return -1;
 196     }
 197     c->zstream.next_in = encoded;
 198     c->zstream.avail_in = len;
 199     c->zstream.next_out = c->decomp_buf;
 200     c->zstream.avail_out = c->decomp_size;
 201     zret = inflate(&(c->zstream), Z_FINISH);
 202     // Z_DATA_ERROR means empty picture
 203     if ((zret != Z_OK) && (zret != Z_STREAM_END) && (zret != Z_DATA_ERROR)) {
 204         av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret);
 205         return -1;
 206     }
 207
 208
 209     if(zret != Z_DATA_ERROR)
 210         decode_rle(c, c->zstream.avail_out);
 211
 212     /* make the palette available on the way out */
 213     if (c->avctx->pix_fmt == PIX_FMT_PAL8) {
 214         memcpy(c->pic.data[1], c->avctx->palctrl->palette, AVPALETTE_SIZE);
 215         if (c->avctx->palctrl->palette_changed) {
 216             c->pic.palette_has_changed = 1;
 217             c->avctx->palctrl->palette_changed = 0;
 218         }
 219     }
 220
 221 #else
 222     av_log(avctx, AV_LOG_ERROR, "BUG! Zlib support not compiled in frame decoder.\n");
 223     return -1;
 224 #endif
 225
 226     *data_size = sizeof(AVFrame);
 227     *(AVFrame*)data = c->pic;
 228
 229     /* always report that the buffer was completely consumed */
 230     return buf_size;
 231 }
 232
 233
 234
 235 /*
 236  *
 237  * Init tscc decoder
 238  *
 239  */
 240 static int decode_init(AVCodecContext *avctx)
 241 {
 242     CamtasiaContext * const c = (CamtasiaContext *)avctx->priv_data;
 243     int zret; // Zlib return code
 244
 245     c->avctx = avctx;
 246     avctx->has_b_frames = 0;
 247
 248     c->pic.data[0] = NULL;
 249     c->height = avctx->height;
 250
 251     if (avcodec_check_dimensions(avctx, avctx->height, avctx->width) < 0) {
 252         return 1;
 253     }
 254
 255 #ifdef CONFIG_ZLIB
 256     // Needed if zlib unused or init aborted before inflateInit
 257     memset(&(c->zstream), 0, sizeof(z_stream));
 258 #else
 259     av_log(avctx, AV_LOG_ERROR, "Zlib support not compiled.\n");
 260     return 1;
 261 #endif
 262     switch(avctx->bits_per_sample){
 263     case  8: avctx->pix_fmt = PIX_FMT_PAL8; break;
 264     case 16: avctx->pix_fmt = PIX_FMT_RGB555; break;
 265     case 24:
 266              avctx->pix_fmt = PIX_FMT_BGR24;
 267              break;
 268     case 32: avctx->pix_fmt = PIX_FMT_RGBA32; break;
 269     default: av_log(avctx, AV_LOG_ERROR, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_sample);
 270              return -1;
 271     }
 272     c->bpp = avctx->bits_per_sample;
 273     c->decomp_size = (avctx->width * c->bpp + (avctx->width + 254) / 255 + 2) * avctx->height + 2;//RLE in the 'best' case
 274
 275     /* Allocate decompression buffer */
 276     if (c->decomp_size) {
 277         if ((c->decomp_buf = av_malloc(c->decomp_size)) == NULL) {
 278             av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
 279             return 1;
 280         }
 281     }
 282
 283 #ifdef CONFIG_ZLIB
 284     c->zstream.zalloc = Z_NULL;
 285     c->zstream.zfree = Z_NULL;
 286     c->zstream.opaque = Z_NULL;
 287     zret = inflateInit(&(c->zstream));
 288     if (zret != Z_OK) {
 289         av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
 290         return 1;
 291     }
 292 #endif
 293
 294     return 0;
 295 }
 296
 297
 298
 299 /*
 300  *
 301  * Uninit tscc decoder
 302  *
 303  */
 304 static int decode_end(AVCodecContext *avctx)
 305 {
 306     CamtasiaContext * const c = (CamtasiaContext *)avctx->priv_data;
 307
 308     av_freep(&c->decomp_buf);
 309
 310     if (c->pic.data[0])
 311         avctx->release_buffer(avctx, &c->pic);
 312 #ifdef CONFIG_ZLIB
 313     inflateEnd(&(c->zstream));
 314 #endif
 315
 316     return 0;
 317 }
 318
 319 AVCodec tscc_decoder = {
 320         "camtasia",
 321         CODEC_TYPE_VIDEO,
 322         CODEC_ID_TSCC,
 323         sizeof(CamtasiaContext),
 324         decode_init,
 325         NULL,
 326         decode_end,
 327         decode_frame,
 328         CODEC_CAP_DR1,
 329 };
 330