2 * Microsoft Video-1 Encoder
3 * Copyright (c) 2009 Konstantin Shishkov
5 * This file is part of FFmpeg.
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.
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.
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
24 * Microsoft Video-1 encoder
29 #include "bytestream.h"
30 #include "libavutil/lfg.h"
32 #include "libavutil/imgutils.h"
36 typedef struct Msvideo1EncContext {
37 AVCodecContext *avctx;
60 #define SKIP_PREFIX 0x8400
61 #define SKIPS_MAX 0x0FFF
62 #define MKRGB555(in, off) ((in[off] << 10) | (in[off + 1] << 5) | (in[off + 2]))
64 static const int remap[16] = { 0, 1, 4, 5, 2, 3, 6, 7, 8, 9, 12, 13, 10, 11, 14, 15 };
66 static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
67 const AVFrame *pict, int *got_packet)
69 Msvideo1EncContext * const c = avctx->priv_data;
70 AVFrame * const p = &c->pic;
76 int i, j, k, x, y, ret;
79 if ((ret = ff_alloc_packet2(avctx, pkt, avctx->width*avctx->height*9 + FF_MIN_BUFFER_SIZE)) < 0)
85 c->prev = av_malloc(avctx->width * 3 * (avctx->height + 3));
86 prevptr = c->prev + avctx->width * 3 * (FFALIGN(avctx->height, 4) - 1);
87 src = (uint16_t*)(p->data[0] + p->linesize[0]*(FFALIGN(avctx->height, 4) - 1));
88 if(c->keyint >= avctx->keyint_min)
93 for(y = 0; y < avctx->height; y += 4){
94 for(x = 0; x < avctx->width; x += 4){
95 int bestmode = MODE_SKIP;
96 int bestscore = INT_MAX;
100 for(j = 0; j < 4; j++){
101 for(i = 0; i < 4; i++){
102 uint16_t val = src[x + i - j*p->linesize[0]/2];
103 for(k = 0; k < 3; k++){
104 c->block[(i + j*4)*3 + k] =
105 c->block2[remap[i + j*4]*3 + k] = (val >> (10-k*5)) & 0x1F;
111 for(j = 0; j < 4; j++){
112 for(i = 0; i < 4*3; i++){
113 int t = prevptr[x*3 + i - j*3*avctx->width] - c->block[i + j*4*3];
117 bestscore /= p->quality;
119 // try to find optimal value to fill whole 4x4 block
121 ff_init_elbg(c->block, 3, 16, c->avg, 1, 1, c->output, &c->rnd);
122 ff_do_elbg (c->block, 3, 16, c->avg, 1, 1, c->output, &c->rnd);
123 if(c->avg[0] == 1) // red component = 1 will be written as skip code
125 for(j = 0; j < 4; j++){
126 for(i = 0; i < 4; i++){
127 for(k = 0; k < 3; k++){
128 int t = c->avg[k] - c->block[(i+j*4)*3+k];
135 if(score < bestscore){
137 bestmode = MODE_FILL;
139 // search for optimal filling of 2-color block
141 ff_init_elbg(c->block, 3, 16, c->codebook, 2, 1, c->output, &c->rnd);
142 ff_do_elbg (c->block, 3, 16, c->codebook, 2, 1, c->output, &c->rnd);
143 // last output value should be always 1, swap codebooks if needed
145 for(i = 0; i < 3; i++)
146 FFSWAP(uint8_t, c->codebook[i], c->codebook[i+3]);
147 for(i = 0; i < 16; i++)
150 for(j = 0; j < 4; j++){
151 for(i = 0; i < 4; i++){
152 for(k = 0; k < 3; k++){
153 int t = c->codebook[c->output[i+j*4]*3 + k] - c->block[i*3+k+j*4*3];
160 if(score < bestscore){
162 bestmode = MODE_2COL;
164 // search for optimal filling of 2-color 2x2 subblocks
166 for(i = 0; i < 4; i++){
167 ff_init_elbg(c->block2 + i*4*3, 3, 4, c->codebook2 + i*2*3, 2, 1, c->output2 + i*4, &c->rnd);
168 ff_do_elbg (c->block2 + i*4*3, 3, 4, c->codebook2 + i*2*3, 2, 1, c->output2 + i*4, &c->rnd);
170 // last value should be always 1, swap codebooks if needed
172 for(i = 0; i < 3; i++)
173 FFSWAP(uint8_t, c->codebook2[i+18], c->codebook2[i+21]);
174 for(i = 12; i < 16; i++)
177 for(j = 0; j < 4; j++){
178 for(i = 0; i < 4; i++){
179 for(k = 0; k < 3; k++){
180 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];
187 if(score < bestscore){
189 bestmode = MODE_8COL;
192 if(bestmode == MODE_SKIP){
196 if((bestmode != MODE_SKIP && skips) || skips == SKIPS_MAX){
197 bytestream_put_le16(&dst, skips | SKIP_PREFIX);
203 bytestream_put_le16(&dst, MKRGB555(c->avg,0) | 0x8000);
204 for(j = 0; j < 4; j++)
205 for(i = 0; i < 4; i++)
206 for(k = 0; k < 3; k++)
207 prevptr[x*3 + i*3 + k - j*3*avctx->width] = c->avg[k];
210 for(j = 0; j < 4; j++){
211 for(i = 0; i < 4; i++){
212 flags |= (c->output[i + j*4]^1) << (i + j*4);
213 for(k = 0; k < 3; k++)
214 prevptr[x*3 + i*3 + k - j*3*avctx->width] = c->codebook[c->output[i + j*4]*3 + k];
217 bytestream_put_le16(&dst, flags);
218 bytestream_put_le16(&dst, MKRGB555(c->codebook, 0));
219 bytestream_put_le16(&dst, MKRGB555(c->codebook, 3));
222 for(j = 0; j < 4; j++){
223 for(i = 0; i < 4; i++){
224 flags |= (c->output2[remap[i + j*4]]^1) << (i + j*4);
225 for(k = 0; k < 3; k++)
226 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];
229 bytestream_put_le16(&dst, flags);
230 bytestream_put_le16(&dst, MKRGB555(c->codebook2, 0) | 0x8000);
231 for(i = 3; i < 24; i += 3)
232 bytestream_put_le16(&dst, MKRGB555(c->codebook2, i));
236 src -= p->linesize[0] << 1;
237 prevptr -= avctx->width * 3 * 4;
240 bytestream_put_le16(&dst, skips | SKIP_PREFIX);
242 bytestream_put_byte(&dst, 0);
243 bytestream_put_byte(&dst, 0);
251 p->pict_type= keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
252 p->key_frame= keyframe;
253 if (keyframe) pkt->flags |= AV_PKT_FLAG_KEY;
254 pkt->size = dst - buf;
264 static av_cold int encode_init(AVCodecContext *avctx)
266 Msvideo1EncContext * const c = avctx->priv_data;
269 if (av_image_check_size(avctx->width, avctx->height, 0, avctx) < 0) {
272 if((avctx->width&3) || (avctx->height&3)){
273 av_log(avctx, AV_LOG_ERROR, "width and height must be multiplies of 4\n");
277 avcodec_get_frame_defaults(&c->pic);
278 avctx->coded_frame = (AVFrame*)&c->pic;
279 avctx->bits_per_coded_sample = 16;
281 c->keyint = avctx->keyint_min;
282 av_lfg_init(&c->rnd, 1);
292 static av_cold int encode_end(AVCodecContext *avctx)
294 Msvideo1EncContext * const c = avctx->priv_data;
301 AVCodec ff_msvideo1_encoder = {
303 .type = AVMEDIA_TYPE_VIDEO,
304 .id = AV_CODEC_ID_MSVIDEO1,
305 .priv_data_size = sizeof(Msvideo1EncContext),
307 .encode2 = encode_frame,
309 .pix_fmts = (const enum AVPixelFormat[]){AV_PIX_FMT_RGB555, AV_PIX_FMT_NONE},
310 .long_name = NULL_IF_CONFIG_SMALL("Microsoft Video-1"),