extern/ffmpeg/libavcodec/kmvc.c

   1 /*
   2  * KMVC decoder
   3  * Copyright (c) 2006 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  18  *
  19  */
  20
  21 /**
  22  * @file kmvc.c
  23  * Karl Morton's Video Codec decoder
  24  */
  25
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28
  29 #include "common.h"
  30 #include "avcodec.h"
  31
  32 #define KMVC_KEYFRAME 0x80
  33 #define KMVC_PALETTE  0x40
  34 #define KMVC_METHOD   0x0F
  35
  36 /*
  37  * Decoder context
  38  */
  39 typedef struct KmvcContext {
  40     AVCodecContext *avctx;
  41     AVFrame pic;
  42
  43     int setpal;
  44     int palsize;
  45     uint32_t pal[256];
  46     uint8_t *cur, *prev;
  47     uint8_t *frm0, *frm1;
  48 } KmvcContext;
  49
  50 typedef struct BitBuf {
  51     int bits;
  52     int bitbuf;
  53 } BitBuf;
  54
  55 #define BLK(data, x, y)  data[(x) + (y) * 320]
  56
  57 #define kmvc_init_getbits(bb, src)  bb.bits = 7; bb.bitbuf = *src++;
  58
  59 #define kmvc_getbit(bb, src, res) {\
  60     res = 0; \
  61     if (bb.bitbuf & (1 << bb.bits)) res = 1; \
  62     bb.bits--; \
  63     if(bb.bits == -1) { \
  64         bb.bitbuf = *src++; \
  65         bb.bits = 7; \
  66     } \
  67 }
  68
  69 static void kmvc_decode_intra_8x8(KmvcContext * ctx, uint8_t * src, int w, int h)
  70 {
  71     BitBuf bb;
  72     int res, val;
  73     int i, j;
  74     int bx, by;
  75     int l0x, l1x, l0y, l1y;
  76     int mx, my;
  77
  78     kmvc_init_getbits(bb, src);
  79
  80     for (by = 0; by < h; by += 8)
  81         for (bx = 0; bx < w; bx += 8) {
  82             kmvc_getbit(bb, src, res);
  83             if (!res) {         // fill whole 8x8 block
  84                 val = *src++;
  85                 for (i = 0; i < 64; i++)
  86                     BLK(ctx->cur, bx + (i & 0x7), by + (i >> 3)) = val;
  87             } else {            // handle four 4x4 subblocks
  88                 for (i = 0; i < 4; i++) {
  89                     l0x = bx + (i & 1) * 4;
  90                     l0y = by + (i & 2) * 2;
  91                     kmvc_getbit(bb, src, res);
  92                     if (!res) {
  93                         kmvc_getbit(bb, src, res);
  94                         if (!res) {     // fill whole 4x4 block
  95                             val = *src++;
  96                             for (j = 0; j < 16; j++)
  97                                 BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) = val;
  98                         } else {        // copy block from already decoded place
  99                             val = *src++;
 100                             mx = val & 0xF;
 101                             my = val >> 4;
 102                             for (j = 0; j < 16; j++)
 103                                 BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) =
 104                                     BLK(ctx->cur, l0x + (j & 3) - mx, l0y + (j >> 2) - my);
 105                         }
 106                     } else {    // descend to 2x2 sub-sub-blocks
 107                         for (j = 0; j < 4; j++) {
 108                             l1x = l0x + (j & 1) * 2;
 109                             l1y = l0y + (j & 2);
 110                             kmvc_getbit(bb, src, res);
 111                             if (!res) {
 112                                 kmvc_getbit(bb, src, res);
 113                                 if (!res) {     // fill whole 2x2 block
 114                                     val = *src++;
 115                                     BLK(ctx->cur, l1x, l1y) = val;
 116                                     BLK(ctx->cur, l1x + 1, l1y) = val;
 117                                     BLK(ctx->cur, l1x, l1y + 1) = val;
 118                                     BLK(ctx->cur, l1x + 1, l1y + 1) = val;
 119                                 } else {        // copy block from already decoded place
 120                                     val = *src++;
 121                                     mx = val & 0xF;
 122                                     my = val >> 4;
 123                                     BLK(ctx->cur, l1x, l1y) = BLK(ctx->cur, l1x - mx, l1y - my);
 124                                     BLK(ctx->cur, l1x + 1, l1y) =
 125                                         BLK(ctx->cur, l1x + 1 - mx, l1y - my);
 126                                     BLK(ctx->cur, l1x, l1y + 1) =
 127                                         BLK(ctx->cur, l1x - mx, l1y + 1 - my);
 128                                     BLK(ctx->cur, l1x + 1, l1y + 1) =
 129                                         BLK(ctx->cur, l1x + 1 - mx, l1y + 1 - my);
 130                                 }
 131                             } else {    // read values for block
 132                                 BLK(ctx->cur, l1x, l1y) = *src++;
 133                                 BLK(ctx->cur, l1x + 1, l1y) = *src++;
 134                                 BLK(ctx->cur, l1x, l1y + 1) = *src++;
 135                                 BLK(ctx->cur, l1x + 1, l1y + 1) = *src++;
 136                             }
 137                         }
 138                     }
 139                 }
 140             }
 141         }
 142 }
 143
 144 static void kmvc_decode_inter_8x8(KmvcContext * ctx, uint8_t * src, int w, int h)
 145 {
 146     BitBuf bb;
 147     int res, val;
 148     int i, j;
 149     int bx, by;
 150     int l0x, l1x, l0y, l1y;
 151     int mx, my;
 152
 153     kmvc_init_getbits(bb, src);
 154
 155     for (by = 0; by < h; by += 8)
 156         for (bx = 0; bx < w; bx += 8) {
 157             kmvc_getbit(bb, src, res);
 158             if (!res) {
 159                 kmvc_getbit(bb, src, res);
 160                 if (!res) {     // fill whole 8x8 block
 161                     val = *src++;
 162                     for (i = 0; i < 64; i++)
 163                         BLK(ctx->cur, bx + (i & 0x7), by + (i >> 3)) = val;
 164                 } else {        // copy block from previous frame
 165                     for (i = 0; i < 64; i++)
 166                         BLK(ctx->cur, bx + (i & 0x7), by + (i >> 3)) =
 167                             BLK(ctx->prev, bx + (i & 0x7), by + (i >> 3));
 168                 }
 169             } else {            // handle four 4x4 subblocks
 170                 for (i = 0; i < 4; i++) {
 171                     l0x = bx + (i & 1) * 4;
 172                     l0y = by + (i & 2) * 2;
 173                     kmvc_getbit(bb, src, res);
 174                     if (!res) {
 175                         kmvc_getbit(bb, src, res);
 176                         if (!res) {     // fill whole 4x4 block
 177                             val = *src++;
 178                             for (j = 0; j < 16; j++)
 179                                 BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) = val;
 180                         } else {        // copy block
 181                             val = *src++;
 182                             mx = (val & 0xF) - 8;
 183                             my = (val >> 4) - 8;
 184                             for (j = 0; j < 16; j++)
 185                                 BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) =
 186                                     BLK(ctx->prev, l0x + (j & 3) + mx, l0y + (j >> 2) + my);
 187                         }
 188                     } else {    // descend to 2x2 sub-sub-blocks
 189                         for (j = 0; j < 4; j++) {
 190                             l1x = l0x + (j & 1) * 2;
 191                             l1y = l0y + (j & 2);
 192                             kmvc_getbit(bb, src, res);
 193                             if (!res) {
 194                                 kmvc_getbit(bb, src, res);
 195                                 if (!res) {     // fill whole 2x2 block
 196                                     val = *src++;
 197                                     BLK(ctx->cur, l1x, l1y) = val;
 198                                     BLK(ctx->cur, l1x + 1, l1y) = val;
 199                                     BLK(ctx->cur, l1x, l1y + 1) = val;
 200                                     BLK(ctx->cur, l1x + 1, l1y + 1) = val;
 201                                 } else {        // copy block
 202                                     val = *src++;
 203                                     mx = (val & 0xF) - 8;
 204                                     my = (val >> 4) - 8;
 205                                     BLK(ctx->cur, l1x, l1y) = BLK(ctx->prev, l1x + mx, l1y + my);
 206                                     BLK(ctx->cur, l1x + 1, l1y) =
 207                                         BLK(ctx->prev, l1x + 1 + mx, l1y + my);
 208                                     BLK(ctx->cur, l1x, l1y + 1) =
 209                                         BLK(ctx->prev, l1x + mx, l1y + 1 + my);
 210                                     BLK(ctx->cur, l1x + 1, l1y + 1) =
 211                                         BLK(ctx->prev, l1x + 1 + mx, l1y + 1 + my);
 212                                 }
 213                             } else {    // read values for block
 214                                 BLK(ctx->cur, l1x, l1y) = *src++;
 215                                 BLK(ctx->cur, l1x + 1, l1y) = *src++;
 216                                 BLK(ctx->cur, l1x, l1y + 1) = *src++;
 217                                 BLK(ctx->cur, l1x + 1, l1y + 1) = *src++;
 218                             }
 219                         }
 220                     }
 221                 }
 222             }
 223         }
 224 }
 225
 226 static int decode_frame(AVCodecContext * avctx, void *data, int *data_size, uint8_t * buf,
 227                         int buf_size)
 228 {
 229     KmvcContext *const ctx = (KmvcContext *) avctx->priv_data;
 230     uint8_t *out, *src;
 231     int i;
 232     int header;
 233     int blocksize;
 234
 235     if (ctx->pic.data[0])
 236         avctx->release_buffer(avctx, &ctx->pic);
 237
 238     ctx->pic.reference = 1;
 239     ctx->pic.buffer_hints = FF_BUFFER_HINTS_VALID;
 240     if (avctx->get_buffer(avctx, &ctx->pic) < 0) {
 241         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 242         return -1;
 243     }
 244
 245     header = *buf++;
 246
 247     /* blocksize 127 is really palette change event */
 248     if (buf[0] == 127) {
 249         buf += 3;
 250         for (i = 0; i < 127; i++) {
 251             ctx->pal[i + (header & 0x81)] = (buf[0] << 16) | (buf[1] << 8) | buf[2];
 252             buf += 4;
 253         }
 254         buf -= 127 * 4 + 3;
 255     }
 256
 257     if (header & KMVC_KEYFRAME) {
 258         ctx->pic.key_frame = 1;
 259         ctx->pic.pict_type = FF_I_TYPE;
 260     } else {
 261         ctx->pic.key_frame = 0;
 262         ctx->pic.pict_type = FF_P_TYPE;
 263     }
 264
 265     /* if palette has been changed, copy it from palctrl */
 266     if (ctx->avctx->palctrl && ctx->avctx->palctrl->palette_changed) {
 267         memcpy(ctx->pal, ctx->avctx->palctrl->palette, AVPALETTE_SIZE);
 268         ctx->setpal = 1;
 269         ctx->avctx->palctrl->palette_changed = 0;
 270     }
 271
 272     if (header & KMVC_PALETTE) {
 273         ctx->pic.palette_has_changed = 1;
 274         // palette starts from index 1 and has 127 entries
 275         for (i = 1; i <= ctx->palsize; i++) {
 276             ctx->pal[i] = (buf[0] << 16) | (buf[1] << 8) | buf[2];
 277             buf += 3;
 278         }
 279     }
 280
 281     if (ctx->setpal) {
 282         ctx->setpal = 0;
 283         ctx->pic.palette_has_changed = 1;
 284     }
 285
 286     /* make the palette available on the way out */
 287     memcpy(ctx->pic.data[1], ctx->pal, 1024);
 288
 289     blocksize = *buf++;
 290
 291     if (blocksize != 8 && blocksize != 127) {
 292         av_log(avctx, AV_LOG_ERROR, "Block size = %i\n", blocksize);
 293         return -1;
 294     }
 295     memset(ctx->cur, 0, 320 * 200);
 296     switch (header & KMVC_METHOD) {
 297     case 0:
 298     case 1: // used in palette changed event
 299         memcpy(ctx->cur, ctx->prev, 320 * 200);
 300         break;
 301     case 3:
 302         kmvc_decode_intra_8x8(ctx, buf, avctx->width, avctx->height);
 303         break;
 304     case 4:
 305         kmvc_decode_inter_8x8(ctx, buf, avctx->width, avctx->height);
 306         break;
 307     default:
 308         av_log(avctx, AV_LOG_ERROR, "Unknown compression method %i\n", header & KMVC_METHOD);
 309         return -1;
 310     }
 311
 312     out = ctx->pic.data[0];
 313     src = ctx->cur;
 314     for (i = 0; i < avctx->height; i++) {
 315         memcpy(out, src, avctx->width);
 316         src += 320;
 317         out += ctx->pic.linesize[0];
 318     }
 319
 320     /* flip buffers */
 321     if (ctx->cur == ctx->frm0) {
 322         ctx->cur = ctx->frm1;
 323         ctx->prev = ctx->frm0;
 324     } else {
 325         ctx->cur = ctx->frm0;
 326         ctx->prev = ctx->frm1;
 327     }
 328
 329     *data_size = sizeof(AVFrame);
 330     *(AVFrame *) data = ctx->pic;
 331
 332     /* always report that the buffer was completely consumed */
 333     return buf_size;
 334 }
 335
 336
 337
 338 /*
 339  * Init kmvc decoder
 340  */
 341 static int decode_init(AVCodecContext * avctx)
 342 {
 343     KmvcContext *const c = (KmvcContext *) avctx->priv_data;
 344     int i;
 345
 346     c->avctx = avctx;
 347     avctx->has_b_frames = 0;
 348
 349     c->pic.data[0] = NULL;
 350
 351     if (avctx->width > 320 || avctx->height > 200) {
 352         av_log(avctx, AV_LOG_ERROR, "KMVC supports frames <= 320x200\n");
 353         return -1;
 354     }
 355
 356     c->frm0 = av_mallocz(320 * 200);
 357     c->frm1 = av_mallocz(320 * 200);
 358     c->cur = c->frm0;
 359     c->prev = c->frm1;
 360
 361     for (i = 0; i < 256; i++) {
 362         c->pal[i] = i * 0x10101;
 363     }
 364
 365     if (avctx->extradata_size < 12) {
 366         av_log(NULL, 0, "Extradata missing, decoding may not work properly...\n");
 367         c->palsize = 127;
 368     } else {
 369         c->palsize = LE_16(avctx->extradata + 10);
 370     }
 371
 372     if (avctx->extradata_size == 1036) {        // palette in extradata
 373         uint8_t *src = avctx->extradata + 12;
 374         for (i = 0; i < 256; i++) {
 375             c->pal[i] = LE_32(src);
 376             src += 4;
 377         }
 378         c->setpal = 1;
 379         if (c->avctx->palctrl) {
 380             c->avctx->palctrl->palette_changed = 0;
 381         }
 382     }
 383
 384     avctx->pix_fmt = PIX_FMT_PAL8;
 385
 386     return 0;
 387 }
 388
 389
 390
 391 /*
 392  * Uninit kmvc decoder
 393  */
 394 static int decode_end(AVCodecContext * avctx)
 395 {
 396     KmvcContext *const c = (KmvcContext *) avctx->priv_data;
 397
 398     if (c->frm0)
 399         av_free(c->frm0);
 400     if (c->frm1)
 401         av_free(c->frm1);
 402     if (c->pic.data[0])
 403         avctx->release_buffer(avctx, &c->pic);
 404
 405     return 0;
 406 }
 407
 408 AVCodec kmvc_decoder = {
 409     "kmvc",
 410     CODEC_TYPE_VIDEO,
 411     CODEC_ID_KMVC,
 412     sizeof(KmvcContext),
 413     decode_init,
 414     NULL,
 415     decode_end,
 416     decode_frame
 417 };