git.sesse.net Git - ffmpeg/blob - libavcodec/ljpegenc.c

   1 /*
   2  * lossless JPEG encoder
   3  * Copyright (c) 2000, 2001 Fabrice Bellard
   4  * Copyright (c) 2003 Alex Beregszaszi
   5  * Copyright (c) 2003-2004 Michael Niedermayer
   6  *
   7  * Support for external huffman table, various fixes (AVID workaround),
   8  * aspecting, new decode_frame mechanism and apple mjpeg-b support
   9  *                                  by Alex Beregszaszi
  10  *
  11  * This file is part of Libav.
  12  *
  13  * Libav is free software; you can redistribute it and/or
  14  * modify it under the terms of the GNU Lesser General Public
  15  * License as published by the Free Software Foundation; either
  16  * version 2.1 of the License, or (at your option) any later version.
  17  *
  18  * Libav is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21  * Lesser General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU Lesser General Public
  24  * License along with Libav; if not, write to the Free Software
  25  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  26  */
  27
  28 /**
  29  * @file
  30  * lossless JPEG encoder.
  31  */
  32
  33 #include "avcodec.h"
  34 #include "internal.h"
  35 #include "mpegvideo.h"
  36 #include "mjpeg.h"
  37 #include "mjpegenc.h"
  38
  39
  40 static int encode_picture_lossless(AVCodecContext *avctx, AVPacket *pkt,
  41                                    const AVFrame *pict, int *got_packet)
  42 {
  43     MpegEncContext * const s = avctx->priv_data;
  44     MJpegContext * const m = s->mjpeg_ctx;
  45     const int width= s->width;
  46     const int height= s->height;
  47     AVFrame * const p = &s->current_picture.f;
  48     const int predictor= avctx->prediction_method+1;
  49     const int mb_width  = (width  + s->mjpeg_hsample[0] - 1) / s->mjpeg_hsample[0];
  50     const int mb_height = (height + s->mjpeg_vsample[0] - 1) / s->mjpeg_vsample[0];
  51     int ret, max_pkt_size = FF_MIN_BUFFER_SIZE;
  52
  53     if (avctx->pix_fmt == AV_PIX_FMT_BGRA)
  54         max_pkt_size += width * height * 3 * 4;
  55     else {
  56         max_pkt_size += mb_width * mb_height * 3 * 4
  57                         * s->mjpeg_hsample[0] * s->mjpeg_vsample[0];
  58     }
  59     if ((ret = ff_alloc_packet(pkt, max_pkt_size)) < 0) {
  60         av_log(avctx, AV_LOG_ERROR, "Error getting output packet of size %d.\n", max_pkt_size);
  61         return ret;
  62     }
  63
  64     init_put_bits(&s->pb, pkt->data, pkt->size);
  65
  66     *p = *pict;
  67     p->pict_type= AV_PICTURE_TYPE_I;
  68     p->key_frame= 1;
  69
  70     ff_mjpeg_encode_picture_header(s);
  71
  72     s->header_bits= put_bits_count(&s->pb);
  73
  74     if(avctx->pix_fmt == AV_PIX_FMT_BGRA){
  75         int x, y, i;
  76         const int linesize= p->linesize[0];
  77         uint16_t (*buffer)[4]= (void *) s->rd_scratchpad;
  78         int left[3], top[3], topleft[3];
  79
  80         for(i=0; i<3; i++){
  81             buffer[0][i]= 1 << (9 - 1);
  82         }
  83
  84         for(y = 0; y < height; y++) {
  85             const int modified_predictor= y ? predictor : 1;
  86             uint8_t *ptr = p->data[0] + (linesize * y);
  87
  88             if(s->pb.buf_end - s->pb.buf - (put_bits_count(&s->pb)>>3) < width*3*4){
  89                 av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");
  90                 return -1;
  91             }
  92
  93             for(i=0; i<3; i++){
  94                 top[i]= left[i]= topleft[i]= buffer[0][i];
  95             }
  96             for(x = 0; x < width; x++) {
  97                 buffer[x][1] = ptr[4*x+0] - ptr[4*x+1] + 0x100;
  98                 buffer[x][2] = ptr[4*x+2] - ptr[4*x+1] + 0x100;
  99                 buffer[x][0] = (ptr[4*x+0] + 2*ptr[4*x+1] + ptr[4*x+2])>>2;
 100
 101                 for(i=0;i<3;i++) {
 102                     int pred, diff;
 103
 104                     PREDICT(pred, topleft[i], top[i], left[i], modified_predictor);
 105
 106                     topleft[i]= top[i];
 107                     top[i]= buffer[x+1][i];
 108
 109                     left[i]= buffer[x][i];
 110
 111                     diff= ((left[i] - pred + 0x100)&0x1FF) - 0x100;
 112
 113                     if(i==0)
 114                         ff_mjpeg_encode_dc(s, diff, m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly
 115                     else
 116                         ff_mjpeg_encode_dc(s, diff, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
 117                 }
 118             }
 119         }
 120     }else{
 121         int mb_x, mb_y, i;
 122
 123         for(mb_y = 0; mb_y < mb_height; mb_y++) {
 124             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]){
 125                 av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");
 126                 return -1;
 127             }
 128             for(mb_x = 0; mb_x < mb_width; mb_x++) {
 129                 if(mb_x==0 || mb_y==0){
 130                     for(i=0;i<3;i++) {
 131                         uint8_t *ptr;
 132                         int x, y, h, v, linesize;
 133                         h = s->mjpeg_hsample[i];
 134                         v = s->mjpeg_vsample[i];
 135                         linesize= p->linesize[i];
 136
 137                         for(y=0; y<v; y++){
 138                             for(x=0; x<h; x++){
 139                                 int pred;
 140
 141                                 ptr = p->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
 142                                 if(y==0 && mb_y==0){
 143                                     if(x==0 && mb_x==0){
 144                                         pred= 128;
 145                                     }else{
 146                                         pred= ptr[-1];
 147                                     }
 148                                 }else{
 149                                     if(x==0 && mb_x==0){
 150                                         pred= ptr[-linesize];
 151                                     }else{
 152                                         PREDICT(pred, ptr[-linesize-1], ptr[-linesize], ptr[-1], predictor);
 153                                     }
 154                                 }
 155
 156                                 if(i==0)
 157                                     ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly
 158                                 else
 159                                     ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
 160                             }
 161                         }
 162                     }
 163                 }else{
 164                     for(i=0;i<3;i++) {
 165                         uint8_t *ptr;
 166                         int x, y, h, v, linesize;
 167                         h = s->mjpeg_hsample[i];
 168                         v = s->mjpeg_vsample[i];
 169                         linesize= p->linesize[i];
 170
 171                         for(y=0; y<v; y++){
 172                             for(x=0; x<h; x++){
 173                                 int pred;
 174
 175                                 ptr = p->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
 176                                 PREDICT(pred, ptr[-linesize-1], ptr[-linesize], ptr[-1], predictor);
 177
 178                                 if(i==0)
 179                                     ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly
 180                                 else
 181                                     ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
 182                             }
 183                         }
 184                     }
 185                 }
 186             }
 187         }
 188     }
 189
 190     emms_c();
 191
 192     ff_mjpeg_encode_picture_trailer(s);
 193     s->picture_number++;
 194
 195     flush_put_bits(&s->pb);
 196     pkt->size   = put_bits_ptr(&s->pb) - s->pb.buf;
 197     pkt->flags |= AV_PKT_FLAG_KEY;
 198     *got_packet = 1;
 199
 200     return 0;
 201 //    return (put_bits_count(&f->pb)+7)/8;
 202 }
 203
 204
 205 AVCodec ff_ljpeg_encoder = { //FIXME avoid MPV_* lossless JPEG should not need them
 206     .name           = "ljpeg",
 207     .type           = AVMEDIA_TYPE_VIDEO,
 208     .id             = AV_CODEC_ID_LJPEG,
 209     .priv_data_size = sizeof(MpegEncContext),
 210     .init           = ff_MPV_encode_init,
 211     .encode2        = encode_picture_lossless,
 212     .close          = ff_MPV_encode_end,
 213     .long_name      = NULL_IF_CONFIG_SMALL("Lossless JPEG"),
 214 };