| 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 | */ |
| 36 | typedef 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 | |
| 52 | enum 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 | |
| 63 | static const int remap[16] = { 0, 1, 4, 5, 2, 3, 6, 7, 8, 9, 12, 13, 10, 11, 14, 15 }; |
| 64 | |
| 65 | static 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 | */ |
| 260 | static 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 multiples 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 | */ |
| 286 | static 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 | |
| 295 | AVCodec 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 | }; |