ffmpeg/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
  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 "get_bits.h"
  36 #include "huffman.h"
  37 #include "bytestream.h"
  38 #include "bswapdsp.h"
  39 #include "internal.h"
  40 #include "thread.h"
  41
  42 #define FPS_TAG MKTAG('F', 'P', 'S', 'x')
  43 #define VLC_BITS 11
  44
  45 /**
  46  * local variable storage
  47  */
  48 typedef struct FrapsContext {
  49     AVCodecContext *avctx;
  50     BswapDSPContext bdsp;
  51     uint8_t *tmpbuf;
  52     int tmpbuf_size;
  53 } FrapsContext;
  54
  55
  56 /**
  57  * initializes decoder
  58  * @param avctx codec context
  59  * @return 0 on success or negative if fails
  60  */
  61 static av_cold int decode_init(AVCodecContext *avctx)
  62 {
  63     FrapsContext * const s = avctx->priv_data;
  64
  65     s->avctx  = avctx;
  66     s->tmpbuf = NULL;
  67
  68     ff_bswapdsp_init(&s->bdsp);
  69
  70     return 0;
  71 }
  72
  73 /**
  74  * Comparator - our nodes should ascend by count
  75  * but with preserved symbol order
  76  */
  77 static int huff_cmp(const void *va, const void *vb)
  78 {
  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                                const int step)
  89 {
  90     int i, j, ret;
  91     GetBitContext gb;
  92     VLC vlc;
  93     Node nodes[512];
  94
  95     for (i = 0; i < 256; i++)
  96         nodes[i].count = bytestream_get_le32(&src);
  97     size -= 1024;
  98     if ((ret = ff_huff_build_tree(s->avctx, &vlc, 256, VLC_BITS,
  99                                   nodes, huff_cmp,
 100                                   FF_HUFFMAN_FLAG_ZERO_COUNT)) < 0)
 101         return ret;
 102     /* we have built Huffman table and are ready to decode plane */
 103
 104     /* convert bits so they may be used by standard bitreader */
 105     s->bdsp.bswap_buf((uint32_t *) s->tmpbuf,
 106                       (const uint32_t *) src, size >> 2);
 107
 108     init_get_bits(&gb, s->tmpbuf, size * 8);
 109     for (j = 0; j < h; j++) {
 110         for (i = 0; i < w*step; i += step) {
 111             dst[i] = get_vlc2(&gb, vlc.table, VLC_BITS, 3);
 112             /* lines are stored as deltas between previous lines
 113              * and we need to add 0x80 to the first lines of chroma planes
 114              */
 115             if (j)
 116                 dst[i] += dst[i - stride];
 117             else if (Uoff)
 118                 dst[i] += 0x80;
 119             if (get_bits_left(&gb) < 0) {
 120                 ff_free_vlc(&vlc);
 121                 return AVERROR_INVALIDDATA;
 122             }
 123         }
 124         dst += stride;
 125     }
 126     ff_free_vlc(&vlc);
 127     return 0;
 128 }
 129
 130 static int decode_frame(AVCodecContext *avctx,
 131                         void *data, int *got_frame,
 132                         AVPacket *avpkt)
 133 {
 134     FrapsContext * const s = avctx->priv_data;
 135     const uint8_t *buf     = avpkt->data;
 136     int buf_size           = avpkt->size;
 137     ThreadFrame frame = { .f = data };
 138     AVFrame * const f = data;
 139     uint32_t header;
 140     unsigned int version,header_size;
 141     unsigned int x, y;
 142     const uint32_t *buf32;
 143     uint32_t *luma1,*luma2,*cb,*cr;
 144     uint32_t offs[4];
 145     int i, j, ret, is_chroma;
 146     const int planes = 3;
 147     uint8_t *out;
 148
 149     if (buf_size < 4) {
 150         av_log(avctx, AV_LOG_ERROR, "Packet is too short\n");
 151         return AVERROR_INVALIDDATA;
 152     }
 153
 154     header      = AV_RL32(buf);
 155     version     = header & 0xff;
 156     header_size = (header & (1<<30))? 8 : 4; /* bit 30 means pad to 8 bytes */
 157
 158     if (version > 5) {
 159         av_log(avctx, AV_LOG_ERROR,
 160                "This file is encoded with Fraps version %d. " \
 161                "This codec can only decode versions <= 5.\n", version);
 162         return AVERROR_PATCHWELCOME;
 163     }
 164
 165     buf += header_size;
 166
 167     if (version < 2) {
 168         unsigned needed_size = avctx->width * avctx->height * 3;
 169         if (version == 0) needed_size /= 2;
 170         needed_size += header_size;
 171         /* bit 31 means same as previous pic */
 172         if (header & (1U<<31)) {
 173             *got_frame = 0;
 174             return buf_size;
 175         }
 176         if (buf_size != needed_size) {
 177             av_log(avctx, AV_LOG_ERROR,
 178                    "Invalid frame length %d (should be %d)\n",
 179                    buf_size, needed_size);
 180             return AVERROR_INVALIDDATA;
 181         }
 182     } else {
 183         /* skip frame */
 184         if (buf_size == 8) {
 185             *got_frame = 0;
 186             return buf_size;
 187         }
 188         if (AV_RL32(buf) != FPS_TAG || buf_size < planes*1024 + 24) {
 189             av_log(avctx, AV_LOG_ERROR, "Fraps: error in data stream\n");
 190             return AVERROR_INVALIDDATA;
 191         }
 192         for (i = 0; i < planes; i++) {
 193             offs[i] = AV_RL32(buf + 4 + i * 4);
 194             if (offs[i] >= buf_size - header_size || (i && offs[i] <= offs[i - 1] + 1024)) {
 195                 av_log(avctx, AV_LOG_ERROR, "Fraps: plane %i offset is out of bounds\n", i);
 196                 return AVERROR_INVALIDDATA;
 197             }
 198         }
 199         offs[planes] = buf_size - header_size;
 200         for (i = 0; i < planes; i++) {
 201             av_fast_padded_malloc(&s->tmpbuf, &s->tmpbuf_size, offs[i + 1] - offs[i] - 1024);
 202             if (!s->tmpbuf)
 203                 return AVERROR(ENOMEM);
 204         }
 205     }
 206
 207     f->pict_type = AV_PICTURE_TYPE_I;
 208     f->key_frame = 1;
 209
 210     avctx->pix_fmt = version & 1 ? AV_PIX_FMT_BGR24 : AV_PIX_FMT_YUVJ420P;
 211     avctx->color_range = version & 1 ? AVCOL_RANGE_UNSPECIFIED
 212                                      : AVCOL_RANGE_JPEG;
 213     avctx->colorspace = version & 1 ? AVCOL_SPC_UNSPECIFIED : AVCOL_SPC_BT709;
 214
 215     if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)
 216         return ret;
 217
 218     switch (version) {
 219     case 0:
 220     default:
 221         /* Fraps v0 is a reordered YUV420 */
 222         if (((avctx->width % 8) != 0) || ((avctx->height % 2) != 0)) {
 223             av_log(avctx, AV_LOG_ERROR, "Invalid frame size %dx%d\n",
 224                    avctx->width, avctx->height);
 225             return AVERROR_INVALIDDATA;
 226         }
 227
 228         buf32 = (const uint32_t*)buf;
 229         for (y = 0; y < avctx->height / 2; y++) {
 230             luma1 = (uint32_t*)&f->data[0][  y * 2      * f->linesize[0] ];
 231             luma2 = (uint32_t*)&f->data[0][ (y * 2 + 1) * f->linesize[0] ];
 232             cr    = (uint32_t*)&f->data[1][  y          * f->linesize[1] ];
 233             cb    = (uint32_t*)&f->data[2][  y          * f->linesize[2] ];
 234             for (x = 0; x < avctx->width; x += 8) {
 235                 *luma1++ = *buf32++;
 236                 *luma1++ = *buf32++;
 237                 *luma2++ = *buf32++;
 238                 *luma2++ = *buf32++;
 239                 *cr++    = *buf32++;
 240                 *cb++    = *buf32++;
 241             }
 242         }
 243         break;
 244
 245     case 1:
 246         /* Fraps v1 is an upside-down BGR24 */
 247             for (y = 0; y<avctx->height; y++)
 248                 memcpy(&f->data[0][(avctx->height - y - 1) * f->linesize[0]],
 249                        &buf[y * avctx->width * 3],
 250                        3 * avctx->width);
 251         break;
 252
 253     case 2:
 254     case 4:
 255         /**
 256          * Fraps v2 is Huffman-coded YUV420 planes
 257          * Fraps v4 is virtually the same
 258          */
 259         for (i = 0; i < planes; i++) {
 260             is_chroma = !!i;
 261             if ((ret = fraps2_decode_plane(s, f->data[i], f->linesize[i],
 262                                            avctx->width  >> is_chroma,
 263                                            avctx->height >> is_chroma,
 264                                            buf + offs[i], offs[i + 1] - offs[i],
 265                                            is_chroma, 1)) < 0) {
 266                 av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
 267                 return ret;
 268             }
 269         }
 270         break;
 271     case 3:
 272     case 5:
 273         /* Virtually the same as version 4, but is for RGB24 */
 274         for (i = 0; i < planes; i++) {
 275             if ((ret = fraps2_decode_plane(s, f->data[0] + i + (f->linesize[0] * (avctx->height - 1)),
 276                                            -f->linesize[0], avctx->width, avctx->height,
 277                                            buf + offs[i], offs[i + 1] - offs[i], 0, 3)) < 0) {
 278                 av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
 279                 return ret;
 280             }
 281         }
 282         out = f->data[0];
 283         // convert pseudo-YUV into real RGB
 284         for (j = 0; j < avctx->height; j++) {
 285             uint8_t *line_end = out + 3*avctx->width;
 286             while (out < line_end) {
 287                 out[0]  += out[1];
 288                 out[2]  += out[1];
 289                 out += 3;
 290             }
 291             out += f->linesize[0] - 3*avctx->width;
 292         }
 293         break;
 294     }
 295
 296     *got_frame = 1;
 297
 298     return buf_size;
 299 }
 300
 301
 302 /**
 303  * closes decoder
 304  * @param avctx codec context
 305  * @return 0 on success or negative if fails
 306  */
 307 static av_cold int decode_end(AVCodecContext *avctx)
 308 {
 309     FrapsContext *s = (FrapsContext*)avctx->priv_data;
 310
 311     av_freep(&s->tmpbuf);
 312     return 0;
 313 }
 314
 315
 316 AVCodec ff_fraps_decoder = {
 317     .name           = "fraps",
 318     .long_name      = NULL_IF_CONFIG_SMALL("Fraps"),
 319     .type           = AVMEDIA_TYPE_VIDEO,
 320     .id             = AV_CODEC_ID_FRAPS,
 321     .priv_data_size = sizeof(FrapsContext),
 322     .init           = decode_init,
 323     .close          = decode_end,
 324     .decode         = decode_frame,
 325     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
 326 };