libavcodec/fraps.c
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00001 /*
00002  * Fraps FPS1 decoder
00003  * Copyright (c) 2005 Roine Gustafsson
00004  * Copyright (c) 2006 Konstantin Shishkov
00005  *
00006  * This file is part of FFmpeg.
00007  *
00008  * FFmpeg is free software; you can redistribute it and/or
00009  * modify it under the terms of the GNU Lesser General Public
00010  * License as published by the Free Software Foundation; either
00011  * version 2.1 of the License, or (at your option) any later version.
00012  *
00013  * FFmpeg is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00016  * Lesser General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU Lesser General Public
00019  * License along with FFmpeg; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00021  */
00022 
00034 #include "avcodec.h"
00035 #include "get_bits.h"
00036 #include "huffman.h"
00037 #include "bytestream.h"
00038 #include "dsputil.h"
00039 
00040 #define FPS_TAG MKTAG('F', 'P', 'S', 'x')
00041 
00045 typedef struct FrapsContext{
00046     AVCodecContext *avctx;
00047     AVFrame frame;
00048     uint8_t *tmpbuf;
00049     int tmpbuf_size;
00050     DSPContext dsp;
00051 } FrapsContext;
00052 
00053 
00059 static av_cold int decode_init(AVCodecContext *avctx)
00060 {
00061     FrapsContext * const s = avctx->priv_data;
00062 
00063     avcodec_get_frame_defaults(&s->frame);
00064     avctx->coded_frame = (AVFrame*)&s->frame;
00065 
00066     s->avctx = avctx;
00067     s->tmpbuf = NULL;
00068 
00069     dsputil_init(&s->dsp, avctx);
00070 
00071     return 0;
00072 }
00073 
00078 static int huff_cmp(const void *va, const void *vb){
00079     const Node *a = va, *b = vb;
00080     return (a->count - b->count)*256 + a->sym - b->sym;
00081 }
00082 
00086 static int fraps2_decode_plane(FrapsContext *s, uint8_t *dst, int stride, int w,
00087                                int h, const uint8_t *src, int size, int Uoff,
00088                                const int step)
00089 {
00090     int i, j;
00091     GetBitContext gb;
00092     VLC vlc;
00093     Node nodes[512];
00094 
00095     for(i = 0; i < 256; i++)
00096         nodes[i].count = bytestream_get_le32(&src);
00097     size -= 1024;
00098     if (ff_huff_build_tree(s->avctx, &vlc, 256, nodes, huff_cmp,
00099                            FF_HUFFMAN_FLAG_ZERO_COUNT) < 0)
00100         return -1;
00101     /* we have built Huffman table and are ready to decode plane */
00102 
00103     /* convert bits so they may be used by standard bitreader */
00104     s->dsp.bswap_buf((uint32_t *)s->tmpbuf, (const uint32_t *)src, size >> 2);
00105 
00106     init_get_bits(&gb, s->tmpbuf, size * 8);
00107     for(j = 0; j < h; j++){
00108         for(i = 0; i < w*step; i += step){
00109             dst[i] = get_vlc2(&gb, vlc.table, 9, 3);
00110             /* lines are stored as deltas between previous lines
00111              * and we need to add 0x80 to the first lines of chroma planes
00112              */
00113             if(j) dst[i] += dst[i - stride];
00114             else if(Uoff) dst[i] += 0x80;
00115             if (get_bits_left(&gb) < 0) {
00116                 ff_free_vlc(&vlc);
00117                 return AVERROR_INVALIDDATA;
00118             }
00119         }
00120         dst += stride;
00121     }
00122     ff_free_vlc(&vlc);
00123     return 0;
00124 }
00125 
00126 static int decode_frame(AVCodecContext *avctx,
00127                         void *data, int *data_size,
00128                         AVPacket *avpkt)
00129 {
00130     const uint8_t *buf = avpkt->data;
00131     int buf_size = avpkt->size;
00132     FrapsContext * const s = avctx->priv_data;
00133     AVFrame *frame = data;
00134     AVFrame * const f = (AVFrame*)&s->frame;
00135     uint32_t header;
00136     unsigned int version,header_size;
00137     unsigned int x, y;
00138     const uint32_t *buf32;
00139     uint32_t *luma1,*luma2,*cb,*cr;
00140     uint32_t offs[4];
00141     int i, j, is_chroma;
00142     const int planes = 3;
00143     enum PixelFormat pix_fmt;
00144 
00145     header = AV_RL32(buf);
00146     version = header & 0xff;
00147     header_size = (header & (1<<30))? 8 : 4; /* bit 30 means pad to 8 bytes */
00148 
00149     if (version > 5) {
00150         av_log(avctx, AV_LOG_ERROR,
00151                "This file is encoded with Fraps version %d. " \
00152                "This codec can only decode versions <= 5.\n", version);
00153         return -1;
00154     }
00155 
00156     buf += header_size;
00157 
00158     if (version < 2) {
00159         unsigned needed_size = avctx->width*avctx->height*3;
00160         if (version == 0) needed_size /= 2;
00161         needed_size += header_size;
00162         if (buf_size != needed_size && buf_size != header_size) {
00163             av_log(avctx, AV_LOG_ERROR,
00164                    "Invalid frame length %d (should be %d)\n",
00165                    buf_size, needed_size);
00166             return -1;
00167         }
00168     }
00169 
00170     f->pict_type = AV_PICTURE_TYPE_I;
00171     f->key_frame = 1;
00172     f->reference = 3;
00173     f->buffer_hints = FF_BUFFER_HINTS_VALID |
00174                       FF_BUFFER_HINTS_PRESERVE |
00175                       FF_BUFFER_HINTS_REUSABLE;
00176 
00177     pix_fmt = version & 1 ? PIX_FMT_BGR24 : PIX_FMT_YUVJ420P;
00178     if (avctx->pix_fmt != pix_fmt && f->data[0]) {
00179         avctx->release_buffer(avctx, f);
00180     }
00181     avctx->pix_fmt = pix_fmt;
00182 
00183     switch(version) {
00184     case 0:
00185     default:
00186         /* Fraps v0 is a reordered YUV420 */
00187         if ( (avctx->width % 8) != 0 || (avctx->height % 2) != 0 ) {
00188             av_log(avctx, AV_LOG_ERROR, "Invalid frame size %dx%d\n",
00189                    avctx->width, avctx->height);
00190             return -1;
00191         }
00192 
00193         if (avctx->reget_buffer(avctx, f)) {
00194             av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
00195             return -1;
00196         }
00197         /* bit 31 means same as previous pic */
00198         if (header & (1U<<31)) {
00199             f->pict_type = AV_PICTURE_TYPE_P;
00200             f->key_frame = 0;
00201         } else {
00202             buf32=(const uint32_t*)buf;
00203             for(y=0; y<avctx->height/2; y++){
00204                 luma1=(uint32_t*)&f->data[0][ y*2*f->linesize[0] ];
00205                 luma2=(uint32_t*)&f->data[0][ (y*2+1)*f->linesize[0] ];
00206                 cr=(uint32_t*)&f->data[1][ y*f->linesize[1] ];
00207                 cb=(uint32_t*)&f->data[2][ y*f->linesize[2] ];
00208                 for(x=0; x<avctx->width; x+=8){
00209                     *luma1++ = *buf32++;
00210                     *luma1++ = *buf32++;
00211                     *luma2++ = *buf32++;
00212                     *luma2++ = *buf32++;
00213                     *cr++    = *buf32++;
00214                     *cb++    = *buf32++;
00215                 }
00216             }
00217         }
00218         break;
00219 
00220     case 1:
00221         /* Fraps v1 is an upside-down BGR24 */
00222         if (avctx->reget_buffer(avctx, f)) {
00223             av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
00224             return -1;
00225         }
00226         /* bit 31 means same as previous pic */
00227         if (header & (1U<<31)) {
00228             f->pict_type = AV_PICTURE_TYPE_P;
00229             f->key_frame = 0;
00230         } else {
00231             for(y=0; y<avctx->height; y++)
00232                 memcpy(&f->data[0][ (avctx->height-y)*f->linesize[0] ],
00233                        &buf[y*avctx->width*3],
00234                        3*avctx->width);
00235         }
00236         break;
00237 
00238     case 2:
00239     case 4:
00244         if (avctx->reget_buffer(avctx, f)) {
00245             av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
00246             return -1;
00247         }
00248         /* skip frame */
00249         if(buf_size == 8) {
00250             f->pict_type = AV_PICTURE_TYPE_P;
00251             f->key_frame = 0;
00252             break;
00253         }
00254         if (AV_RL32(buf) != FPS_TAG || buf_size < planes*1024 + 24) {
00255             av_log(avctx, AV_LOG_ERROR, "Fraps: error in data stream\n");
00256             return -1;
00257         }
00258         for(i = 0; i < planes; i++) {
00259             offs[i] = AV_RL32(buf + 4 + i * 4);
00260             if(offs[i] >= buf_size || (i && offs[i] <= offs[i - 1] + 1024)) {
00261                 av_log(avctx, AV_LOG_ERROR, "Fraps: plane %i offset is out of bounds\n", i);
00262                 return -1;
00263             }
00264         }
00265         offs[planes] = buf_size;
00266         for(i = 0; i < planes; i++){
00267             is_chroma = !!i;
00268             av_fast_padded_malloc(&s->tmpbuf, &s->tmpbuf_size, offs[i + 1] - offs[i] - 1024);
00269             if (!s->tmpbuf)
00270                 return AVERROR(ENOMEM);
00271             if(fraps2_decode_plane(s, f->data[i], f->linesize[i], avctx->width >> is_chroma,
00272                     avctx->height >> is_chroma, buf + offs[i], offs[i + 1] - offs[i], is_chroma, 1) < 0) {
00273                 av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
00274                 return -1;
00275             }
00276         }
00277         break;
00278     case 3:
00279     case 5:
00280         /* Virtually the same as version 4, but is for RGB24 */
00281         if (avctx->reget_buffer(avctx, f)) {
00282             av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
00283             return -1;
00284         }
00285         /* skip frame */
00286         if(buf_size == 8) {
00287             f->pict_type = AV_PICTURE_TYPE_P;
00288             f->key_frame = 0;
00289             break;
00290         }
00291         if (AV_RL32(buf) != FPS_TAG || buf_size < planes*1024 + 24) {
00292             av_log(avctx, AV_LOG_ERROR, "Fraps: error in data stream\n");
00293             return -1;
00294         }
00295         for(i = 0; i < planes; i++) {
00296             offs[i] = AV_RL32(buf + 4 + i * 4);
00297             if(offs[i] >= buf_size || (i && offs[i] <= offs[i - 1] + 1024)) {
00298                 av_log(avctx, AV_LOG_ERROR, "Fraps: plane %i offset is out of bounds\n", i);
00299                 return -1;
00300             }
00301         }
00302         offs[planes] = buf_size;
00303         for(i = 0; i < planes; i++){
00304             av_fast_padded_malloc(&s->tmpbuf, &s->tmpbuf_size, offs[i + 1] - offs[i] - 1024);
00305             if (!s->tmpbuf)
00306                 return AVERROR(ENOMEM);
00307             if(fraps2_decode_plane(s, f->data[0] + i + (f->linesize[0] * (avctx->height - 1)), -f->linesize[0],
00308                     avctx->width, avctx->height, buf + offs[i], offs[i + 1] - offs[i], 0, 3) < 0) {
00309                 av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
00310                 return -1;
00311             }
00312         }
00313         // convert pseudo-YUV into real RGB
00314         for(j = 0; j < avctx->height; j++){
00315             for(i = 0; i < avctx->width; i++){
00316                 f->data[0][0 + i*3 + j*f->linesize[0]] += f->data[0][1 + i*3 + j*f->linesize[0]];
00317                 f->data[0][2 + i*3 + j*f->linesize[0]] += f->data[0][1 + i*3 + j*f->linesize[0]];
00318             }
00319         }
00320         break;
00321     }
00322 
00323     *frame = *f;
00324     *data_size = sizeof(AVFrame);
00325 
00326     return buf_size;
00327 }
00328 
00329 
00335 static av_cold int decode_end(AVCodecContext *avctx)
00336 {
00337     FrapsContext *s = (FrapsContext*)avctx->priv_data;
00338 
00339     if (s->frame.data[0])
00340         avctx->release_buffer(avctx, &s->frame);
00341 
00342     av_freep(&s->tmpbuf);
00343     return 0;
00344 }
00345 
00346 
00347 AVCodec ff_fraps_decoder = {
00348     .name           = "fraps",
00349     .type           = AVMEDIA_TYPE_VIDEO,
00350     .id             = CODEC_ID_FRAPS,
00351     .priv_data_size = sizeof(FrapsContext),
00352     .init           = decode_init,
00353     .close          = decode_end,
00354     .decode         = decode_frame,
00355     .capabilities   = CODEC_CAP_DR1,
00356     .long_name = NULL_IF_CONFIG_SMALL("Fraps"),
00357 };