1/* 2 * Microsoft Video-1 Encoder 3 * Copyright (c) 2009 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 24 * Microsoft Video-1 encoder 25 */ 26 27#include "avcodec.h" 28#include "internal.h" 29#include "bytestream.h" 30#include "libavutil/lfg.h" 31#include "elbg.h" 32#include "libavutil/imgutils.h" 33/** 34 * Encoder context 35 */ 36typedef struct Msvideo1EncContext { 37 AVCodecContext *avctx; 38 AVLFG rnd; 39 uint8_t *prev; 40 41 int block[16*3]; 42 int block2[16*3]; 43 int codebook[8*3]; 44 int codebook2[8*3]; 45 int output[16*3]; 46 int output2[16*3]; 47 int avg[3]; 48 int bestpos; 49 int keyint; 50} Msvideo1EncContext; 51 52enum MSV1Mode{ 53 MODE_SKIP = 0, 54 MODE_FILL, 55 MODE_2COL, 56 MODE_8COL, 57}; 58 59#define SKIP_PREFIX 0x8400 60#define SKIPS_MAX 0x03FF 61#define MKRGB555(in, off) (((in)[off] << 10) | ((in)[(off) + 1] << 5) | ((in)[(off) + 2])) 62 63static const int remap[16] = { 0, 1, 4, 5, 2, 3, 6, 7, 8, 9, 12, 13, 10, 11, 14, 15 }; 64 65static int encode_frame(AVCodecContext *avctx, AVPacket *pkt, 66 const AVFrame *pict, int *got_packet) 67{ 68 Msvideo1EncContext * const c = avctx->priv_data; 69 const AVFrame *p = pict; 70 uint16_t *src; 71 uint8_t *prevptr; 72 uint8_t *dst, *buf; 73 int keyframe = 0; 74 int no_skips = 1; 75 int i, j, k, x, y, ret; 76 int skips = 0; 77 int quality = 24; 78 79 if ((ret = ff_alloc_packet2(avctx, pkt, avctx->width*avctx->height*9 + FF_MIN_BUFFER_SIZE)) < 0) 80 return ret; 81 dst= buf= pkt->data; 82 83 if(!c->prev) 84 c->prev = av_malloc(avctx->width * 3 * (avctx->height + 3)); 85 prevptr = c->prev + avctx->width * 3 * (FFALIGN(avctx->height, 4) - 1); 86 src = (uint16_t*)(p->data[0] + p->linesize[0]*(FFALIGN(avctx->height, 4) - 1)); 87 if(c->keyint >= avctx->keyint_min) 88 keyframe = 1; 89 90 91 for(y = 0; y < avctx->height; y += 4){ 92 for(x = 0; x < avctx->width; x += 4){ 93 int bestmode = MODE_SKIP; 94 int bestscore = INT_MAX; 95 int flags = 0; 96 int score; 97 98 for(j = 0; j < 4; j++){ 99 for(i = 0; i < 4; i++){ 100 uint16_t val = src[x + i - j*p->linesize[0]/2]; 101 for(k = 0; k < 3; k++){ 102 c->block[(i + j*4)*3 + k] = 103 c->block2[remap[i + j*4]*3 + k] = (val >> (10-k*5)) & 0x1F; 104 } 105 } 106 } 107 if(!keyframe){ 108 bestscore = 0; 109 for(j = 0; j < 4; j++){ 110 for(i = 0; i < 4*3; i++){ 111 int t = prevptr[x*3 + i - j*3*avctx->width] - c->block[i + j*4*3]; 112 bestscore += t*t; 113 } 114 } 115 bestscore /= quality; 116 } 117 // try to find optimal value to fill whole 4x4 block 118 score = 0; 119 avpriv_init_elbg(c->block, 3, 16, c->avg, 1, 1, c->output, &c->rnd); 120 avpriv_do_elbg (c->block, 3, 16, c->avg, 1, 1, c->output, &c->rnd); 121 if(c->avg[0] == 1) // red component = 1 will be written as skip code 122 c->avg[0] = 0; 123 for(j = 0; j < 4; j++){ 124 for(i = 0; i < 4; i++){ 125 for(k = 0; k < 3; k++){ 126 int t = c->avg[k] - c->block[(i+j*4)*3+k]; 127 score += t*t; 128 } 129 } 130 } 131 score /= quality; 132 score += 2; 133 if(score < bestscore){ 134 bestscore = score; 135 bestmode = MODE_FILL; 136 } 137 // search for optimal filling of 2-color block 138 score = 0; 139 avpriv_init_elbg(c->block, 3, 16, c->codebook, 2, 1, c->output, &c->rnd); 140 avpriv_do_elbg (c->block, 3, 16, c->codebook, 2, 1, c->output, &c->rnd); 141 // last output value should be always 1, swap codebooks if needed 142 if(!c->output[15]){ 143 for(i = 0; i < 3; i++) 144 FFSWAP(uint8_t, c->codebook[i], c->codebook[i+3]); 145 for(i = 0; i < 16; i++) 146 c->output[i] ^= 1; 147 } 148 for(j = 0; j < 4; j++){ 149 for(i = 0; i < 4; i++){ 150 for(k = 0; k < 3; k++){ 151 int t = c->codebook[c->output[i+j*4]*3 + k] - c->block[i*3+k+j*4*3]; 152 score += t*t; 153 } 154 } 155 } 156 score /= quality; 157 score += 6; 158 if(score < bestscore){ 159 bestscore = score; 160 bestmode = MODE_2COL; 161 } 162 // search for optimal filling of 2-color 2x2 subblocks 163 score = 0; 164 for(i = 0; i < 4; i++){ 165 avpriv_init_elbg(c->block2 + i*4*3, 3, 4, c->codebook2 + i*2*3, 2, 1, c->output2 + i*4, &c->rnd); 166 avpriv_do_elbg (c->block2 + i*4*3, 3, 4, c->codebook2 + i*2*3, 2, 1, c->output2 + i*4, &c->rnd); 167 } 168 // last value should be always 1, swap codebooks if needed 169 if(!c->output2[15]){ 170 for(i = 0; i < 3; i++) 171 FFSWAP(uint8_t, c->codebook2[i+18], c->codebook2[i+21]); 172 for(i = 12; i < 16; i++) 173 c->output2[i] ^= 1; 174 } 175 for(j = 0; j < 4; j++){ 176 for(i = 0; i < 4; i++){ 177 for(k = 0; k < 3; k++){ 178 int t = c->codebook2[(c->output2[remap[i+j*4]] + (i&2) + (j&2)*2)*3+k] - c->block[i*3+k + j*4*3]; 179 score += t*t; 180 } 181 } 182 } 183 score /= quality; 184 score += 18; 185 if(score < bestscore){ 186 bestscore = score; 187 bestmode = MODE_8COL; 188 } 189 190 if(bestmode == MODE_SKIP){ 191 skips++; 192 no_skips = 0; 193 } 194 if((bestmode != MODE_SKIP && skips) || skips == SKIPS_MAX){ 195 bytestream_put_le16(&dst, skips | SKIP_PREFIX); 196 skips = 0; 197 } 198 199 switch(bestmode){ 200 case MODE_FILL: 201 bytestream_put_le16(&dst, MKRGB555(c->avg,0) | 0x8000); 202 for(j = 0; j < 4; j++) 203 for(i = 0; i < 4; i++) 204 for(k = 0; k < 3; k++) 205 prevptr[x*3 + i*3 + k - j*3*avctx->width] = c->avg[k]; 206 break; 207 case MODE_2COL: 208 for(j = 0; j < 4; j++){ 209 for(i = 0; i < 4; i++){ 210 flags |= (c->output[i + j*4]^1) << (i + j*4); 211 for(k = 0; k < 3; k++) 212 prevptr[x*3 + i*3 + k - j*3*avctx->width] = c->codebook[c->output[i + j*4]*3 + k]; 213 } 214 } 215 bytestream_put_le16(&dst, flags); 216 bytestream_put_le16(&dst, MKRGB555(c->codebook, 0)); 217 bytestream_put_le16(&dst, MKRGB555(c->codebook, 3)); 218 break; 219 case MODE_8COL: 220 for(j = 0; j < 4; j++){ 221 for(i = 0; i < 4; i++){ 222 flags |= (c->output2[remap[i + j*4]]^1) << (i + j*4); 223 for(k = 0; k < 3; k++) 224 prevptr[x*3 + i*3 + k - j*3*avctx->width] = c->codebook2[(c->output2[remap[i+j*4]] + (i&2) + (j&2)*2)*3 + k]; 225 } 226 } 227 bytestream_put_le16(&dst, flags); 228 bytestream_put_le16(&dst, MKRGB555(c->codebook2, 0) | 0x8000); 229 for(i = 3; i < 24; i += 3) 230 bytestream_put_le16(&dst, MKRGB555(c->codebook2, i)); 231 break; 232 } 233 } 234 src -= p->linesize[0] << 1; 235 prevptr -= avctx->width * 3 * 4; 236 } 237 if(skips) 238 bytestream_put_le16(&dst, skips | SKIP_PREFIX); 239 //EOF 240 bytestream_put_byte(&dst, 0); 241 bytestream_put_byte(&dst, 0); 242 243 if(no_skips) 244 keyframe = 1; 245 if(keyframe) 246 c->keyint = 0; 247 else 248 c->keyint++; 249 if (keyframe) pkt->flags |= AV_PKT_FLAG_KEY; 250 pkt->size = dst - buf; 251 *got_packet = 1; 252 253 return 0; 254} 255 256 257/** 258 * init encoder 259 */ 260static av_cold int encode_init(AVCodecContext *avctx) 261{ 262 Msvideo1EncContext * const c = avctx->priv_data; 263 264 c->avctx = avctx; 265 if (av_image_check_size(avctx->width, avctx->height, 0, avctx) < 0) { 266 return -1; 267 } 268 if((avctx->width&3) || (avctx->height&3)){ 269 av_log(avctx, AV_LOG_ERROR, "width and height must be multiplies of 4\n"); 270 return -1; 271 } 272 273 avctx->bits_per_coded_sample = 16; 274 275 c->keyint = avctx->keyint_min; 276 av_lfg_init(&c->rnd, 1); 277 278 return 0; 279} 280 281 282 283/** 284 * Uninit encoder 285 */ 286static av_cold int encode_end(AVCodecContext *avctx) 287{ 288 Msvideo1EncContext * const c = avctx->priv_data; 289 290 av_freep(&c->prev); 291 292 return 0; 293} 294 295AVCodec ff_msvideo1_encoder = { 296 .name = "msvideo1", 297 .long_name = NULL_IF_CONFIG_SMALL("Microsoft Video-1"), 298 .type = AVMEDIA_TYPE_VIDEO, 299 .id = AV_CODEC_ID_MSVIDEO1, 300 .priv_data_size = sizeof(Msvideo1EncContext), 301 .init = encode_init, 302 .encode2 = encode_frame, 303 .close = encode_end, 304 .pix_fmts = (const enum AVPixelFormat[]){AV_PIX_FMT_RGB555, AV_PIX_FMT_NONE}, 305}; 306