libavcodec/zmbvenc.c

   1 /*
   2  * Zip Motion Blocks Video (ZMBV) encoder
   3  * Copyright (c) 2006 Konstantin Shishkov
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file zmbvenc.c
  24  * Zip Motion Blocks Video encoder
  25  */
  26
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29
  30 #include "avcodec.h"
  31
  32 #include <zlib.h>
  33
  34 #define ZMBV_KEYFRAME 1
  35 #define ZMBV_DELTAPAL 2
  36
  37 #define ZMBV_BLOCK 16
  38
  39 /**
  40  * Encoder context
  41  */
  42 typedef struct ZmbvEncContext {
  43     AVCodecContext *avctx;
  44     AVFrame pic;
  45
  46     int range;
  47     uint8_t *comp_buf, *work_buf;
  48     uint8_t pal[768];
  49     uint32_t pal2[256]; //for quick comparisons
  50     uint8_t *prev;
  51     int pstride;
  52     int comp_size;
  53     int keyint, curfrm;
  54     z_stream zstream;
  55 } ZmbvEncContext;
  56
  57 /** Block comparing function
  58  * XXX should be optimized and moved to DSPContext
  59  * TODO handle out of edge ME
  60  */
  61 static inline int block_cmp(uint8_t *src, int stride, uint8_t *src2, int stride2, int bw, int bh)
  62 {
  63     int sum = 0;
  64     int i, j;
  65
  66     for(j = 0; j < bh; j++){
  67         for(i = 0; i < bw; i++)
  68             sum += src[i] ^ src2[i];
  69         src += stride;
  70         src2 += stride2;
  71     }
  72     return sum;
  73 }
  74
  75 /** Motion estimation function
  76  * TODO make better ME decisions
  77  */
  78 static int zmbv_me(ZmbvEncContext *c, uint8_t *src, int sstride, uint8_t *prev, int pstride,
  79                     int x, int y, int *mx, int *my)
  80 {
  81     int dx, dy, tx, ty, tv, bv, bw, bh;
  82
  83     *mx = *my = 0;
  84     bw = FFMIN(ZMBV_BLOCK, c->avctx->width - x);
  85     bh = FFMIN(ZMBV_BLOCK, c->avctx->height - y);
  86     bv = block_cmp(src, sstride, prev, pstride, bw, bh);
  87     if(!bv) return 0;
  88     for(ty = FFMAX(y - c->range, 0); ty < FFMIN(y + c->range, c->avctx->height - bh); ty++){
  89         for(tx = FFMAX(x - c->range, 0); tx < FFMIN(x + c->range, c->avctx->width - bw); tx++){
  90             if(tx == x && ty == y) continue; // we already tested this block
  91             dx = tx - x;
  92             dy = ty - y;
  93             tv = block_cmp(src, sstride, prev + dx + dy*pstride, pstride, bw, bh);
  94             if(tv < bv){
  95                  bv = tv;
  96                  *mx = dx;
  97                  *my = dy;
  98                  if(!bv) return 0;
  99              }
 100          }
 101     }
 102     return bv;
 103 }
 104
 105 static int encode_frame(AVCodecContext *avctx, uint8_t *buf, int buf_size, void *data)
 106 {
 107     ZmbvEncContext * const c = avctx->priv_data;
 108     AVFrame *pict = data;
 109     AVFrame * const p = &c->pic;
 110     uint8_t *src, *prev;
 111     uint32_t *palptr;
 112     int zret = Z_OK;
 113     int len = 0;
 114     int keyframe, chpal;
 115     int fl;
 116     int work_size = 0;
 117     int bw, bh;
 118     int i, j;
 119
 120     keyframe = !c->curfrm;
 121     c->curfrm++;
 122     if(c->curfrm == c->keyint)
 123         c->curfrm = 0;
 124     *p = *pict;
 125     p->pict_type= keyframe ? FF_I_TYPE : FF_P_TYPE;
 126     p->key_frame= keyframe;
 127     chpal = !keyframe && memcmp(p->data[1], c->pal2, 1024);
 128
 129     fl = (keyframe ? ZMBV_KEYFRAME : 0) | (chpal ? ZMBV_DELTAPAL : 0);
 130     *buf++ = fl; len++;
 131     if(keyframe){
 132         deflateReset(&c->zstream);
 133         *buf++ = 0; len++; // hi ver
 134         *buf++ = 1; len++; // lo ver
 135         *buf++ = 1; len++; // comp
 136         *buf++ = 4; len++; // format - 8bpp
 137         *buf++ = ZMBV_BLOCK; len++; // block width
 138         *buf++ = ZMBV_BLOCK; len++; // block height
 139     }
 140     palptr = (uint32_t*)p->data[1];
 141     src = p->data[0];
 142     prev = c->prev;
 143     if(chpal){
 144         uint8_t tpal[3];
 145         for(i = 0; i < 256; i++){
 146             AV_WB24(tpal, palptr[i]);
 147             c->work_buf[work_size++] = tpal[0] ^ c->pal[i * 3 + 0];
 148             c->work_buf[work_size++] = tpal[1] ^ c->pal[i * 3 + 1];
 149             c->work_buf[work_size++] = tpal[2] ^ c->pal[i * 3 + 2];
 150             c->pal[i * 3 + 0] = tpal[0];
 151             c->pal[i * 3 + 1] = tpal[1];
 152             c->pal[i * 3 + 2] = tpal[2];
 153         }
 154         memcpy(c->pal2, p->data[1], 1024);
 155     }
 156     if(keyframe){
 157         for(i = 0; i < 256; i++){
 158             AV_WB24(c->pal+(i*3), palptr[i]);
 159         }
 160         memcpy(c->work_buf, c->pal, 768);
 161         memcpy(c->pal2, p->data[1], 1024);
 162         work_size = 768;
 163         for(i = 0; i < avctx->height; i++){
 164             memcpy(c->work_buf + work_size, src, avctx->width);
 165             src += p->linesize[0];
 166             work_size += avctx->width;
 167         }
 168     }else{
 169         int x, y, bh2, bw2;
 170         uint8_t *tsrc, *tprev;
 171         uint8_t *mv;
 172         int mx, my, bv;
 173
 174         bw = (avctx->width + ZMBV_BLOCK - 1) / ZMBV_BLOCK;
 175         bh = (avctx->height + ZMBV_BLOCK - 1) / ZMBV_BLOCK;
 176         mv = c->work_buf + work_size;
 177         memset(c->work_buf + work_size, 0, (bw * bh * 2 + 3) & ~3);
 178         work_size += (bw * bh * 2 + 3) & ~3;
 179         /* for now just XOR'ing */
 180         for(y = 0; y < avctx->height; y += ZMBV_BLOCK) {
 181             bh2 = FFMIN(avctx->height - y, ZMBV_BLOCK);
 182             for(x = 0; x < avctx->width; x += ZMBV_BLOCK, mv += 2) {
 183                 bw2 = FFMIN(avctx->width - x, ZMBV_BLOCK);
 184
 185                 tsrc = src + x;
 186                 tprev = prev + x;
 187
 188                 bv = zmbv_me(c, tsrc, p->linesize[0], tprev, c->pstride, x, y, &mx, &my);
 189                 mv[0] = (mx << 1) | !!bv;
 190                 mv[1] = my << 1;
 191                 tprev += mx + my * c->pstride;
 192                 if(bv){
 193                     for(j = 0; j < bh2; j++){
 194                         for(i = 0; i < bw2; i++)
 195                             c->work_buf[work_size++] = tsrc[i] ^ tprev[i];
 196                         tsrc += p->linesize[0];
 197                         tprev += c->pstride;
 198                     }
 199                 }
 200             }
 201             src += p->linesize[0] * ZMBV_BLOCK;
 202             prev += c->pstride * ZMBV_BLOCK;
 203         }
 204     }
 205     /* save the previous frame */
 206     src = p->data[0];
 207     prev = c->prev;
 208     for(i = 0; i < avctx->height; i++){
 209         memcpy(prev, src, avctx->width);
 210         prev += c->pstride;
 211         src += p->linesize[0];
 212     }
 213
 214     c->zstream.next_in = c->work_buf;
 215     c->zstream.avail_in = work_size;
 216     c->zstream.total_in = 0;
 217
 218     c->zstream.next_out = c->comp_buf;
 219     c->zstream.avail_out = c->comp_size;
 220     c->zstream.total_out = 0;
 221     if((zret = deflate(&c->zstream, Z_SYNC_FLUSH)) != Z_OK){
 222         av_log(avctx, AV_LOG_ERROR, "Error compressing data\n");
 223         return -1;
 224     }
 225
 226     memcpy(buf, c->comp_buf, c->zstream.total_out);
 227     return len + c->zstream.total_out;
 228 }
 229
 230
 231 /**
 232  * Init zmbv encoder
 233  */
 234 static int encode_init(AVCodecContext *avctx)
 235 {
 236     ZmbvEncContext * const c = avctx->priv_data;
 237     int zret; // Zlib return code
 238     int lvl = 9;
 239
 240     c->avctx = avctx;
 241
 242     c->pic.data[0] = NULL;
 243     c->curfrm = 0;
 244     c->keyint = avctx->keyint_min;
 245     c->range = 8;
 246     if(avctx->me_range > 0)
 247         c->range = FFMIN(avctx->me_range, 127);
 248
 249     if(avctx->compression_level >= 0)
 250         lvl = avctx->compression_level;
 251     if(lvl < 0 || lvl > 9){
 252         av_log(avctx, AV_LOG_ERROR, "Compression level should be 0-9, not %i\n", lvl);
 253         return -1;
 254     }
 255
 256     if (avcodec_check_dimensions(avctx, avctx->width, avctx->height) < 0) {
 257         return -1;
 258     }
 259
 260     // Needed if zlib unused or init aborted before deflateInit
 261     memset(&(c->zstream), 0, sizeof(z_stream));
 262     c->comp_size = avctx->width * avctx->height + 1024 +
 263         ((avctx->width + ZMBV_BLOCK - 1) / ZMBV_BLOCK) * ((avctx->height + ZMBV_BLOCK - 1) / ZMBV_BLOCK) * 2 + 4;
 264     if ((c->work_buf = av_malloc(c->comp_size)) == NULL) {
 265         av_log(avctx, AV_LOG_ERROR, "Can't allocate work buffer.\n");
 266         return -1;
 267     }
 268     /* Conservative upper bound taken from zlib v1.2.1 source via lcl.c */
 269     c->comp_size = c->comp_size + ((c->comp_size + 7) >> 3) +
 270                            ((c->comp_size + 63) >> 6) + 11;
 271
 272     /* Allocate compression buffer */
 273     if ((c->comp_buf = av_malloc(c->comp_size)) == NULL) {
 274         av_log(avctx, AV_LOG_ERROR, "Can't allocate compression buffer.\n");
 275         return -1;
 276     }
 277     c->pstride = (avctx->width + 15) & ~15;
 278     if ((c->prev = av_malloc(c->pstride * avctx->height)) == NULL) {
 279         av_log(avctx, AV_LOG_ERROR, "Can't allocate picture.\n");
 280         return -1;
 281     }
 282
 283     c->zstream.zalloc = Z_NULL;
 284     c->zstream.zfree = Z_NULL;
 285     c->zstream.opaque = Z_NULL;
 286     zret = deflateInit(&(c->zstream), lvl);
 287     if (zret != Z_OK) {
 288         av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
 289         return -1;
 290     }
 291
 292     return 0;
 293 }
 294
 295
 296
 297 /**
 298  * Uninit zmbv encoder
 299  */
 300 static int encode_end(AVCodecContext *avctx)
 301 {
 302     ZmbvEncContext * const c = avctx->priv_data;
 303
 304     av_freep(&c->comp_buf);
 305     av_freep(&c->work_buf);
 306
 307     deflateEnd(&(c->zstream));
 308     av_freep(&c->prev);
 309
 310     return 0;
 311 }
 312
 313 AVCodec zmbv_encoder = {
 314     "zmbv",
 315     CODEC_TYPE_VIDEO,
 316     CODEC_ID_ZMBV,
 317     sizeof(ZmbvEncContext),
 318     encode_init,
 319     encode_frame,
 320     encode_end,
 321     .pix_fmts = (enum PixelFormat[]){PIX_FMT_PAL8, -1},
 322 };