libavcodec/fraps.c

   1 /*
   2  * Fraps FPS1 decoder
   3  * Copyright (c) 2005 Roine Gustafsson
   4  * Copyright (c) 2006 Konstantin Shishkov
   5  *
   6  * This file is part of FFmpeg.
   7  *
   8  * FFmpeg is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * FFmpeg is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with FFmpeg; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 /**
  24  * @file fraps.c
  25  * Lossless Fraps 'FPS1' decoder
  26  * @author Roine Gustafsson <roine at users sf net>
  27  * @author Konstantin Shishkov
  28  *
  29  * Codec algorithm for version 0 is taken from Transcode <www.transcoding.org>
  30  *
  31  * Version 2 files support by Konstantin Shishkov
  32  */
  33
  34 #include "avcodec.h"
  35 #include "bitstream.h"
  36 #include "huffman.h"
  37 #include "bytestream.h"
  38 #include "dsputil.h"
  39
  40 #define FPS_TAG MKTAG('F', 'P', 'S', 'x')
  41
  42 /**
  43  * local variable storage
  44  */
  45 typedef struct FrapsContext{
  46     AVCodecContext *avctx;
  47     AVFrame frame;
  48     uint8_t *tmpbuf;
  49     DSPContext dsp;
  50 } FrapsContext;
  51
  52
  53 /**
  54  * initializes decoder
  55  * @param avctx codec context
  56  * @return 0 on success or negative if fails
  57  */
  58 static int decode_init(AVCodecContext *avctx)
  59 {
  60     FrapsContext * const s = avctx->priv_data;
  61
  62     avctx->coded_frame = (AVFrame*)&s->frame;
  63     avctx->pix_fmt= PIX_FMT_NONE; /* set in decode_frame */
  64
  65     s->avctx = avctx;
  66     s->frame.data[0] = NULL;
  67     s->tmpbuf = NULL;
  68
  69     dsputil_init(&s->dsp, avctx);
  70
  71     return 0;
  72 }
  73
  74 /**
  75  * Comparator - our nodes should ascend by count
  76  * but with preserved symbol order
  77  */
  78 static int huff_cmp(const void *va, const void *vb){
  79     const Node *a = va, *b = vb;
  80     return (a->count - b->count)*256 + a->sym - b->sym;
  81 }
  82
  83 /**
  84  * decode Fraps v2 packed plane
  85  */
  86 static int fraps2_decode_plane(FrapsContext *s, uint8_t *dst, int stride, int w,
  87                                int h, const uint8_t *src, int size, int Uoff)
  88 {
  89     int i, j;
  90     GetBitContext gb;
  91     VLC vlc;
  92     Node nodes[512];
  93
  94     for(i = 0; i < 256; i++)
  95         nodes[i].count = bytestream_get_le32(&src);
  96     size -= 1024;
  97     if (ff_huff_build_tree(s->avctx, &vlc, 256, nodes, huff_cmp, 0) < 0)
  98         return -1;
  99     /* we have built Huffman table and are ready to decode plane */
 100
 101     /* convert bits so they may be used by standard bitreader */
 102     s->dsp.bswap_buf(s->tmpbuf, src, size >> 2);
 103
 104     init_get_bits(&gb, s->tmpbuf, size * 8);
 105     for(j = 0; j < h; j++){
 106         for(i = 0; i < w; i++){
 107             dst[i] = get_vlc2(&gb, vlc.table, 9, 3);
 108             /* lines are stored as deltas between previous lines
 109              * and we need to add 0x80 to the first lines of chroma planes
 110              */
 111             if(j) dst[i] += dst[i - stride];
 112             else if(Uoff) dst[i] += 0x80;
 113         }
 114         dst += stride;
 115     }
 116     free_vlc(&vlc);
 117     return 0;
 118 }
 119
 120 /**
 121  * decode a frame
 122  * @param avctx codec context
 123  * @param data output AVFrame
 124  * @param data_size size of output data or 0 if no picture is returned
 125  * @param buf input data frame
 126  * @param buf_size size of input data frame
 127  * @return number of consumed bytes on success or negative if decode fails
 128  */
 129 static int decode_frame(AVCodecContext *avctx,
 130                         void *data, int *data_size,
 131                         const uint8_t *buf, int buf_size)
 132 {
 133     FrapsContext * const s = avctx->priv_data;
 134     AVFrame *frame = data;
 135     AVFrame * const f = (AVFrame*)&s->frame;
 136     uint32_t header;
 137     unsigned int version,header_size;
 138     unsigned int x, y;
 139     const uint32_t *buf32;
 140     uint32_t *luma1,*luma2,*cb,*cr;
 141     uint32_t offs[4];
 142     int i, is_chroma, planes;
 143
 144
 145     header = AV_RL32(buf);
 146     version = header & 0xff;
 147     header_size = (header & (1<<30))? 8 : 4; /* bit 30 means pad to 8 bytes */
 148
 149     if (version > 2 && version != 4) {
 150         av_log(avctx, AV_LOG_ERROR,
 151                "This file is encoded with Fraps version %d. " \
 152                "This codec can only decode version 0, 1, 2 and 4.\n", version);
 153         return -1;
 154     }
 155
 156     buf+=4;
 157     if (header_size == 8)
 158         buf+=4;
 159
 160     switch(version) {
 161     case 0:
 162     default:
 163         /* Fraps v0 is a reordered YUV420 */
 164         avctx->pix_fmt = PIX_FMT_YUV420P;
 165
 166         if ( (buf_size != avctx->width*avctx->height*3/2+header_size) &&
 167              (buf_size != header_size) ) {
 168             av_log(avctx, AV_LOG_ERROR,
 169                    "Invalid frame length %d (should be %d)\n",
 170                    buf_size, avctx->width*avctx->height*3/2+header_size);
 171             return -1;
 172         }
 173
 174         if (( (avctx->width % 8) != 0) || ( (avctx->height % 2) != 0 )) {
 175             av_log(avctx, AV_LOG_ERROR, "Invalid frame size %dx%d\n",
 176                    avctx->width, avctx->height);
 177             return -1;
 178         }
 179
 180         f->reference = 1;
 181         f->buffer_hints = FF_BUFFER_HINTS_VALID |
 182                           FF_BUFFER_HINTS_PRESERVE |
 183                           FF_BUFFER_HINTS_REUSABLE;
 184         if (avctx->reget_buffer(avctx, f)) {
 185             av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
 186             return -1;
 187         }
 188         /* bit 31 means same as previous pic */
 189         f->pict_type = (header & (1<<31))? FF_P_TYPE : FF_I_TYPE;
 190         f->key_frame = f->pict_type == FF_I_TYPE;
 191
 192         if (f->pict_type == FF_I_TYPE) {
 193             buf32=(const uint32_t*)buf;
 194             for(y=0; y<avctx->height/2; y++){
 195                 luma1=(uint32_t*)&f->data[0][ y*2*f->linesize[0] ];
 196                 luma2=(uint32_t*)&f->data[0][ (y*2+1)*f->linesize[0] ];
 197                 cr=(uint32_t*)&f->data[1][ y*f->linesize[1] ];
 198                 cb=(uint32_t*)&f->data[2][ y*f->linesize[2] ];
 199                 for(x=0; x<avctx->width; x+=8){
 200                     *(luma1++) = *(buf32++);
 201                     *(luma1++) = *(buf32++);
 202                     *(luma2++) = *(buf32++);
 203                     *(luma2++) = *(buf32++);
 204                     *(cr++) = *(buf32++);
 205                     *(cb++) = *(buf32++);
 206                 }
 207             }
 208         }
 209         break;
 210
 211     case 1:
 212         /* Fraps v1 is an upside-down BGR24 */
 213         avctx->pix_fmt = PIX_FMT_BGR24;
 214
 215         if ( (buf_size != avctx->width*avctx->height*3+header_size) &&
 216              (buf_size != header_size) ) {
 217             av_log(avctx, AV_LOG_ERROR,
 218                    "Invalid frame length %d (should be %d)\n",
 219                    buf_size, avctx->width*avctx->height*3+header_size);
 220             return -1;
 221         }
 222
 223         f->reference = 1;
 224         f->buffer_hints = FF_BUFFER_HINTS_VALID |
 225                           FF_BUFFER_HINTS_PRESERVE |
 226                           FF_BUFFER_HINTS_REUSABLE;
 227         if (avctx->reget_buffer(avctx, f)) {
 228             av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
 229             return -1;
 230         }
 231         /* bit 31 means same as previous pic */
 232         f->pict_type = (header & (1<<31))? FF_P_TYPE : FF_I_TYPE;
 233         f->key_frame = f->pict_type == FF_I_TYPE;
 234
 235         if (f->pict_type == FF_I_TYPE) {
 236             for(y=0; y<avctx->height; y++)
 237                 memcpy(&f->data[0][ (avctx->height-y)*f->linesize[0] ],
 238                        &buf[y*avctx->width*3],
 239                        f->linesize[0]);
 240         }
 241         break;
 242
 243     case 2:
 244     case 4:
 245         /**
 246          * Fraps v2 is Huffman-coded YUV420 planes
 247          * Fraps v4 is virtually the same
 248          */
 249         avctx->pix_fmt = PIX_FMT_YUV420P;
 250         planes = 3;
 251         f->reference = 1;
 252         f->buffer_hints = FF_BUFFER_HINTS_VALID |
 253                           FF_BUFFER_HINTS_PRESERVE |
 254                           FF_BUFFER_HINTS_REUSABLE;
 255         if (avctx->reget_buffer(avctx, f)) {
 256             av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
 257             return -1;
 258         }
 259         /* skip frame */
 260         if(buf_size == 8) {
 261             f->pict_type = FF_P_TYPE;
 262             f->key_frame = 0;
 263             break;
 264         }
 265         f->pict_type = FF_I_TYPE;
 266         f->key_frame = 1;
 267         if ((AV_RL32(buf) != FPS_TAG)||(buf_size < (planes*1024 + 24))) {
 268             av_log(avctx, AV_LOG_ERROR, "Fraps: error in data stream\n");
 269             return -1;
 270         }
 271         for(i = 0; i < planes; i++) {
 272             offs[i] = AV_RL32(buf + 4 + i * 4);
 273             if(offs[i] >= buf_size || (i && offs[i] <= offs[i - 1] + 1024)) {
 274                 av_log(avctx, AV_LOG_ERROR, "Fraps: plane %i offset is out of bounds\n", i);
 275                 return -1;
 276             }
 277         }
 278         offs[planes] = buf_size;
 279         for(i = 0; i < planes; i++){
 280             is_chroma = !!i;
 281             s->tmpbuf = av_realloc(s->tmpbuf, offs[i + 1] - offs[i] - 1024 + FF_INPUT_BUFFER_PADDING_SIZE);
 282             if(fraps2_decode_plane(s, f->data[i], f->linesize[i], avctx->width >> is_chroma,
 283                     avctx->height >> is_chroma, buf + offs[i], offs[i + 1] - offs[i], is_chroma) < 0) {
 284                 av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
 285                 return -1;
 286             }
 287         }
 288         break;
 289     }
 290
 291     *frame = *f;
 292     *data_size = sizeof(AVFrame);
 293
 294     return buf_size;
 295 }
 296
 297
 298 /**
 299  * closes decoder
 300  * @param avctx codec context
 301  * @return 0 on success or negative if fails
 302  */
 303 static int decode_end(AVCodecContext *avctx)
 304 {
 305     FrapsContext *s = (FrapsContext*)avctx->priv_data;
 306
 307     if (s->frame.data[0])
 308         avctx->release_buffer(avctx, &s->frame);
 309
 310     av_freep(&s->tmpbuf);
 311     return 0;
 312 }
 313
 314
 315 AVCodec fraps_decoder = {
 316     "fraps",
 317     CODEC_TYPE_VIDEO,
 318     CODEC_ID_FRAPS,
 319     sizeof(FrapsContext),
 320     decode_init,
 321     NULL,
 322     decode_end,
 323     decode_frame,
 324     CODEC_CAP_DR1,
 325 };