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libavcodec/ljpegenc.c

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00001 /*
00002  * lossless JPEG encoder
00003  * Copyright (c) 2000, 2001 Fabrice Bellard
00004  * Copyright (c) 2003 Alex Beregszaszi
00005  * Copyright (c) 2003-2004 Michael Niedermayer
00006  *
00007  * Support for external huffman table, various fixes (AVID workaround),
00008  * aspecting, new decode_frame mechanism and apple mjpeg-b support
00009  *                                  by Alex Beregszaszi
00010  *
00011  * This file is part of FFmpeg.
00012  *
00013  * FFmpeg is free software; you can redistribute it and/or
00014  * modify it under the terms of the GNU Lesser General Public
00015  * License as published by the Free Software Foundation; either
00016  * version 2.1 of the License, or (at your option) any later version.
00017  *
00018  * FFmpeg is distributed in the hope that it will be useful,
00019  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00020  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00021  * Lesser General Public License for more details.
00022  *
00023  * You should have received a copy of the GNU Lesser General Public
00024  * License along with FFmpeg; if not, write to the Free Software
00025  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00026  */
00027 
00033 #include "avcodec.h"
00034 #include "dsputil.h"
00035 #include "mpegvideo.h"
00036 #include "mjpeg.h"
00037 #include "mjpegenc.h"
00038 
00039 
00040 static int encode_picture_lossless(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){
00041     MpegEncContext * const s = avctx->priv_data;
00042     MJpegContext * const m = s->mjpeg_ctx;
00043     AVFrame *pict = data;
00044     const int width= s->width;
00045     const int height= s->height;
00046     AVFrame * const p= (AVFrame*)&s->current_picture;
00047     const int predictor= avctx->prediction_method+1;
00048 
00049     init_put_bits(&s->pb, buf, buf_size);
00050 
00051     *p = *pict;
00052     p->pict_type= FF_I_TYPE;
00053     p->key_frame= 1;
00054 
00055     ff_mjpeg_encode_picture_header(s);
00056 
00057     s->header_bits= put_bits_count(&s->pb);
00058 
00059     if(avctx->pix_fmt == PIX_FMT_BGRA){
00060         int x, y, i;
00061         const int linesize= p->linesize[0];
00062         uint16_t (*buffer)[4]= (void *) s->rd_scratchpad;
00063         int left[3], top[3], topleft[3];
00064 
00065         for(i=0; i<3; i++){
00066             buffer[0][i]= 1 << (9 - 1);
00067         }
00068 
00069         for(y = 0; y < height; y++) {
00070             const int modified_predictor= y ? predictor : 1;
00071             uint8_t *ptr = p->data[0] + (linesize * y);
00072 
00073             if(s->pb.buf_end - s->pb.buf - (put_bits_count(&s->pb)>>3) < width*3*4){
00074                 av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");
00075                 return -1;
00076             }
00077 
00078             for(i=0; i<3; i++){
00079                 top[i]= left[i]= topleft[i]= buffer[0][i];
00080             }
00081             for(x = 0; x < width; x++) {
00082                 buffer[x][1] = ptr[4*x+0] - ptr[4*x+1] + 0x100;
00083                 buffer[x][2] = ptr[4*x+2] - ptr[4*x+1] + 0x100;
00084                 buffer[x][0] = (ptr[4*x+0] + 2*ptr[4*x+1] + ptr[4*x+2])>>2;
00085 
00086                 for(i=0;i<3;i++) {
00087                     int pred, diff;
00088 
00089                     PREDICT(pred, topleft[i], top[i], left[i], modified_predictor);
00090 
00091                     topleft[i]= top[i];
00092                     top[i]= buffer[x+1][i];
00093 
00094                     left[i]= buffer[x][i];
00095 
00096                     diff= ((left[i] - pred + 0x100)&0x1FF) - 0x100;
00097 
00098                     if(i==0)
00099                         ff_mjpeg_encode_dc(s, diff, m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly
00100                     else
00101                         ff_mjpeg_encode_dc(s, diff, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
00102                 }
00103             }
00104         }
00105     }else{
00106         int mb_x, mb_y, i;
00107         const int mb_width  = (width  + s->mjpeg_hsample[0] - 1) / s->mjpeg_hsample[0];
00108         const int mb_height = (height + s->mjpeg_vsample[0] - 1) / s->mjpeg_vsample[0];
00109 
00110         for(mb_y = 0; mb_y < mb_height; mb_y++) {
00111             if(s->pb.buf_end - s->pb.buf - (put_bits_count(&s->pb)>>3) < mb_width * 4 * 3 * s->mjpeg_hsample[0] * s->mjpeg_vsample[0]){
00112                 av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");
00113                 return -1;
00114             }
00115             for(mb_x = 0; mb_x < mb_width; mb_x++) {
00116                 if(mb_x==0 || mb_y==0){
00117                     for(i=0;i<3;i++) {
00118                         uint8_t *ptr;
00119                         int x, y, h, v, linesize;
00120                         h = s->mjpeg_hsample[i];
00121                         v = s->mjpeg_vsample[i];
00122                         linesize= p->linesize[i];
00123 
00124                         for(y=0; y<v; y++){
00125                             for(x=0; x<h; x++){
00126                                 int pred;
00127 
00128                                 ptr = p->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
00129                                 if(y==0 && mb_y==0){
00130                                     if(x==0 && mb_x==0){
00131                                         pred= 128;
00132                                     }else{
00133                                         pred= ptr[-1];
00134                                     }
00135                                 }else{
00136                                     if(x==0 && mb_x==0){
00137                                         pred= ptr[-linesize];
00138                                     }else{
00139                                         PREDICT(pred, ptr[-linesize-1], ptr[-linesize], ptr[-1], predictor);
00140                                     }
00141                                 }
00142 
00143                                 if(i==0)
00144                                     ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly
00145                                 else
00146                                     ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
00147                             }
00148                         }
00149                     }
00150                 }else{
00151                     for(i=0;i<3;i++) {
00152                         uint8_t *ptr;
00153                         int x, y, h, v, linesize;
00154                         h = s->mjpeg_hsample[i];
00155                         v = s->mjpeg_vsample[i];
00156                         linesize= p->linesize[i];
00157 
00158                         for(y=0; y<v; y++){
00159                             for(x=0; x<h; x++){
00160                                 int pred;
00161 
00162                                 ptr = p->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
00163 //printf("%d %d %d %d %8X\n", mb_x, mb_y, x, y, ptr);
00164                                 PREDICT(pred, ptr[-linesize-1], ptr[-linesize], ptr[-1], predictor);
00165 
00166                                 if(i==0)
00167                                     ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly
00168                                 else
00169                                     ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
00170                             }
00171                         }
00172                     }
00173                 }
00174             }
00175         }
00176     }
00177 
00178     emms_c();
00179 
00180     ff_mjpeg_encode_picture_trailer(s);
00181     s->picture_number++;
00182 
00183     flush_put_bits(&s->pb);
00184     return put_bits_ptr(&s->pb) - s->pb.buf;
00185 //    return (put_bits_count(&f->pb)+7)/8;
00186 }
00187 
00188 
00189 AVCodec ljpeg_encoder = { //FIXME avoid MPV_* lossless JPEG should not need them
00190     "ljpeg",
00191     AVMEDIA_TYPE_VIDEO,
00192     CODEC_ID_LJPEG,
00193     sizeof(MpegEncContext),
00194     MPV_encode_init,
00195     encode_picture_lossless,
00196     MPV_encode_end,
00197     .long_name = NULL_IF_CONFIG_SMALL("Lossless JPEG"),
00198 };

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