yading@10: /*
yading@10:  * Microsoft Video-1 Encoder
yading@10:  * Copyright (c) 2009 Konstantin Shishkov
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * Microsoft Video-1 encoder
yading@10:  */
yading@10: 
yading@10: #include "avcodec.h"
yading@10: #include "internal.h"
yading@10: #include "bytestream.h"
yading@10: #include "libavutil/lfg.h"
yading@10: #include "elbg.h"
yading@10: #include "libavutil/imgutils.h"
yading@10: /**
yading@10:  * Encoder context
yading@10:  */
yading@10: typedef struct Msvideo1EncContext {
yading@10:     AVCodecContext *avctx;
yading@10:     AVFrame pic;
yading@10:     AVLFG rnd;
yading@10:     uint8_t *prev;
yading@10: 
yading@10:     int block[16*3];
yading@10:     int block2[16*3];
yading@10:     int codebook[8*3];
yading@10:     int codebook2[8*3];
yading@10:     int output[16*3];
yading@10:     int output2[16*3];
yading@10:     int avg[3];
yading@10:     int bestpos;
yading@10:     int keyint;
yading@10: } Msvideo1EncContext;
yading@10: 
yading@10: enum MSV1Mode{
yading@10:     MODE_SKIP = 0,
yading@10:     MODE_FILL,
yading@10:     MODE_2COL,
yading@10:     MODE_8COL,
yading@10: };
yading@10: 
yading@10: #define SKIP_PREFIX 0x8400
yading@10: #define SKIPS_MAX 0x0FFF
yading@10: #define MKRGB555(in, off) ((in[off] << 10) | (in[off + 1] << 5) | (in[off + 2]))
yading@10: 
yading@10: static const int remap[16] = { 0, 1, 4, 5, 2, 3, 6, 7, 8, 9, 12, 13, 10, 11, 14, 15 };
yading@10: 
yading@10: static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
yading@10:                                const AVFrame *pict, int *got_packet)
yading@10: {
yading@10:     Msvideo1EncContext * const c = avctx->priv_data;
yading@10:     AVFrame * const p = &c->pic;
yading@10:     uint16_t *src;
yading@10:     uint8_t *prevptr;
yading@10:     uint8_t *dst, *buf;
yading@10:     int keyframe = 0;
yading@10:     int no_skips = 1;
yading@10:     int i, j, k, x, y, ret;
yading@10:     int skips = 0;
yading@10: 
yading@10:     if ((ret = ff_alloc_packet2(avctx, pkt, avctx->width*avctx->height*9 + FF_MIN_BUFFER_SIZE)) < 0)
yading@10:         return ret;
yading@10:     dst= buf= pkt->data;
yading@10: 
yading@10:     *p = *pict;
yading@10:     if(!c->prev)
yading@10:         c->prev = av_malloc(avctx->width * 3 * (avctx->height + 3));
yading@10:     prevptr = c->prev + avctx->width * 3 * (FFALIGN(avctx->height, 4) - 1);
yading@10:     src = (uint16_t*)(p->data[0] + p->linesize[0]*(FFALIGN(avctx->height, 4) - 1));
yading@10:     if(c->keyint >= avctx->keyint_min)
yading@10:         keyframe = 1;
yading@10: 
yading@10:     p->quality = 24;
yading@10: 
yading@10:     for(y = 0; y < avctx->height; y += 4){
yading@10:         for(x = 0; x < avctx->width; x += 4){
yading@10:             int bestmode = MODE_SKIP;
yading@10:             int bestscore = INT_MAX;
yading@10:             int flags = 0;
yading@10:             int score;
yading@10: 
yading@10:             for(j = 0; j < 4; j++){
yading@10:                 for(i = 0; i < 4; i++){
yading@10:                     uint16_t val = src[x + i - j*p->linesize[0]/2];
yading@10:                     for(k = 0; k < 3; k++){
yading@10:                         c->block[(i + j*4)*3 + k] =
yading@10:                         c->block2[remap[i + j*4]*3 + k] = (val >> (10-k*5)) & 0x1F;
yading@10:                     }
yading@10:                 }
yading@10:             }
yading@10:             if(!keyframe){
yading@10:                 bestscore = 0;
yading@10:                 for(j = 0; j < 4; j++){
yading@10:                     for(i = 0; i < 4*3; i++){
yading@10:                         int t = prevptr[x*3 + i - j*3*avctx->width] - c->block[i + j*4*3];
yading@10:                         bestscore += t*t;
yading@10:                     }
yading@10:                 }
yading@10:                 bestscore /= p->quality;
yading@10:             }
yading@10:             // try to find optimal value to fill whole 4x4 block
yading@10:             score = 0;
yading@10:             ff_init_elbg(c->block, 3, 16, c->avg, 1, 1, c->output, &c->rnd);
yading@10:             ff_do_elbg  (c->block, 3, 16, c->avg, 1, 1, c->output, &c->rnd);
yading@10:             if(c->avg[0] == 1) // red component = 1 will be written as skip code
yading@10:                 c->avg[0] = 0;
yading@10:             for(j = 0; j < 4; j++){
yading@10:                 for(i = 0; i < 4; i++){
yading@10:                     for(k = 0; k < 3; k++){
yading@10:                         int t = c->avg[k] - c->block[(i+j*4)*3+k];
yading@10:                         score += t*t;
yading@10:                     }
yading@10:                 }
yading@10:             }
yading@10:             score /= p->quality;
yading@10:             score += 2;
yading@10:             if(score < bestscore){
yading@10:                 bestscore = score;
yading@10:                 bestmode = MODE_FILL;
yading@10:             }
yading@10:             // search for optimal filling of 2-color block
yading@10:             score = 0;
yading@10:             ff_init_elbg(c->block, 3, 16, c->codebook, 2, 1, c->output, &c->rnd);
yading@10:             ff_do_elbg  (c->block, 3, 16, c->codebook, 2, 1, c->output, &c->rnd);
yading@10:             // last output value should be always 1, swap codebooks if needed
yading@10:             if(!c->output[15]){
yading@10:                 for(i = 0; i < 3; i++)
yading@10:                     FFSWAP(uint8_t, c->codebook[i], c->codebook[i+3]);
yading@10:                 for(i = 0; i < 16; i++)
yading@10:                     c->output[i] ^= 1;
yading@10:             }
yading@10:             for(j = 0; j < 4; j++){
yading@10:                 for(i = 0; i < 4; i++){
yading@10:                     for(k = 0; k < 3; k++){
yading@10:                         int t = c->codebook[c->output[i+j*4]*3 + k] - c->block[i*3+k+j*4*3];
yading@10:                         score += t*t;
yading@10:                     }
yading@10:                 }
yading@10:             }
yading@10:             score /= p->quality;
yading@10:             score += 6;
yading@10:             if(score < bestscore){
yading@10:                 bestscore = score;
yading@10:                 bestmode = MODE_2COL;
yading@10:             }
yading@10:             // search for optimal filling of 2-color 2x2 subblocks
yading@10:             score = 0;
yading@10:             for(i = 0; i < 4; i++){
yading@10:                 ff_init_elbg(c->block2 + i*4*3, 3, 4, c->codebook2 + i*2*3, 2, 1, c->output2 + i*4, &c->rnd);
yading@10:                 ff_do_elbg  (c->block2 + i*4*3, 3, 4, c->codebook2 + i*2*3, 2, 1, c->output2 + i*4, &c->rnd);
yading@10:             }
yading@10:             // last value should be always 1, swap codebooks if needed
yading@10:             if(!c->output2[15]){
yading@10:                 for(i = 0; i < 3; i++)
yading@10:                     FFSWAP(uint8_t, c->codebook2[i+18], c->codebook2[i+21]);
yading@10:                 for(i = 12; i < 16; i++)
yading@10:                     c->output2[i] ^= 1;
yading@10:             }
yading@10:             for(j = 0; j < 4; j++){
yading@10:                 for(i = 0; i < 4; i++){
yading@10:                     for(k = 0; k < 3; k++){
yading@10:                         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];
yading@10:                         score += t*t;
yading@10:                     }
yading@10:                 }
yading@10:             }
yading@10:             score /= p->quality;
yading@10:             score += 18;
yading@10:             if(score < bestscore){
yading@10:                 bestscore = score;
yading@10:                 bestmode = MODE_8COL;
yading@10:             }
yading@10: 
yading@10:             if(bestmode == MODE_SKIP){
yading@10:                 skips++;
yading@10:                 no_skips = 0;
yading@10:             }
yading@10:             if((bestmode != MODE_SKIP && skips) || skips == SKIPS_MAX){
yading@10:                 bytestream_put_le16(&dst, skips | SKIP_PREFIX);
yading@10:                 skips = 0;
yading@10:             }
yading@10: 
yading@10:             switch(bestmode){
yading@10:             case MODE_FILL:
yading@10:                 bytestream_put_le16(&dst, MKRGB555(c->avg,0) | 0x8000);
yading@10:                 for(j = 0; j < 4; j++)
yading@10:                     for(i = 0; i < 4; i++)
yading@10:                         for(k = 0; k < 3; k++)
yading@10:                             prevptr[x*3 + i*3 + k - j*3*avctx->width] = c->avg[k];
yading@10:                 break;
yading@10:             case MODE_2COL:
yading@10:                 for(j = 0; j < 4; j++){
yading@10:                     for(i = 0; i < 4; i++){
yading@10:                         flags |= (c->output[i + j*4]^1) << (i + j*4);
yading@10:                         for(k = 0; k < 3; k++)
yading@10:                             prevptr[x*3 + i*3 + k - j*3*avctx->width] = c->codebook[c->output[i + j*4]*3 + k];
yading@10:                     }
yading@10:                 }
yading@10:                 bytestream_put_le16(&dst, flags);
yading@10:                 bytestream_put_le16(&dst, MKRGB555(c->codebook, 0));
yading@10:                 bytestream_put_le16(&dst, MKRGB555(c->codebook, 3));
yading@10:                 break;
yading@10:             case MODE_8COL:
yading@10:                 for(j = 0; j < 4; j++){
yading@10:                     for(i = 0; i < 4; i++){
yading@10:                         flags |= (c->output2[remap[i + j*4]]^1) << (i + j*4);
yading@10:                         for(k = 0; k < 3; k++)
yading@10:                             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];
yading@10:                     }
yading@10:                 }
yading@10:                 bytestream_put_le16(&dst, flags);
yading@10:                 bytestream_put_le16(&dst, MKRGB555(c->codebook2, 0) | 0x8000);
yading@10:                 for(i = 3; i < 24; i += 3)
yading@10:                     bytestream_put_le16(&dst, MKRGB555(c->codebook2, i));
yading@10:                 break;
yading@10:             }
yading@10:         }
yading@10:         src     -= p->linesize[0] << 1;
yading@10:         prevptr -= avctx->width * 3 * 4;
yading@10:     }
yading@10:     if(skips)
yading@10:         bytestream_put_le16(&dst, skips | SKIP_PREFIX);
yading@10:     //EOF
yading@10:     bytestream_put_byte(&dst, 0);
yading@10:     bytestream_put_byte(&dst, 0);
yading@10: 
yading@10:     if(no_skips)
yading@10:         keyframe = 1;
yading@10:     if(keyframe)
yading@10:         c->keyint = 0;
yading@10:     else
yading@10:         c->keyint++;
yading@10:     p->pict_type= keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
yading@10:     p->key_frame= keyframe;
yading@10:     if (keyframe) pkt->flags |= AV_PKT_FLAG_KEY;
yading@10:     pkt->size = dst - buf;
yading@10:     *got_packet = 1;
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: 
yading@10: /**
yading@10:  * init encoder
yading@10:  */
yading@10: static av_cold int encode_init(AVCodecContext *avctx)
yading@10: {
yading@10:     Msvideo1EncContext * const c = avctx->priv_data;
yading@10: 
yading@10:     c->avctx = avctx;
yading@10:     if (av_image_check_size(avctx->width, avctx->height, 0, avctx) < 0) {
yading@10:         return -1;
yading@10:     }
yading@10:     if((avctx->width&3) || (avctx->height&3)){
yading@10:         av_log(avctx, AV_LOG_ERROR, "width and height must be multiplies of 4\n");
yading@10:         return -1;
yading@10:     }
yading@10: 
yading@10:     avcodec_get_frame_defaults(&c->pic);
yading@10:     avctx->coded_frame = (AVFrame*)&c->pic;
yading@10:     avctx->bits_per_coded_sample = 16;
yading@10: 
yading@10:     c->keyint = avctx->keyint_min;
yading@10:     av_lfg_init(&c->rnd, 1);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: 
yading@10: 
yading@10: /**
yading@10:  * Uninit encoder
yading@10:  */
yading@10: static av_cold int encode_end(AVCodecContext *avctx)
yading@10: {
yading@10:     Msvideo1EncContext * const c = avctx->priv_data;
yading@10: 
yading@10:     av_freep(&c->prev);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: AVCodec ff_msvideo1_encoder = {
yading@10:     .name           = "msvideo1",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_MSVIDEO1,
yading@10:     .priv_data_size = sizeof(Msvideo1EncContext),
yading@10:     .init           = encode_init,
yading@10:     .encode2        = encode_frame,
yading@10:     .close          = encode_end,
yading@10:     .pix_fmts = (const enum AVPixelFormat[]){AV_PIX_FMT_RGB555, AV_PIX_FMT_NONE},
yading@10:     .long_name = NULL_IF_CONFIG_SMALL("Microsoft Video-1"),
yading@10: };