summaryrefslogtreecommitdiff
path: root/libavcodec/ljpegenc.c
blob: 9eeb6f202b9eb3920a960555b929f7966a40de83 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
/*
 * lossless JPEG encoder
 * Copyright (c) 2000, 2001 Fabrice Bellard
 * Copyright (c) 2003 Alex Beregszaszi
 * Copyright (c) 2003-2004 Michael Niedermayer
 *
 * Support for external huffman table, various fixes (AVID workaround),
 * aspecting, new decode_frame mechanism and apple mjpeg-b support
 *                                  by Alex Beregszaszi
 *
 * This file is part of Libav.
 *
 * Libav is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * Libav is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with Libav; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * lossless JPEG encoder.
 */

#include "avcodec.h"
#include "dsputil.h"
#include "mpegvideo.h"
#include "mjpeg.h"
#include "mjpegenc.h"


static int encode_picture_lossless(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){
    MpegEncContext * const s = avctx->priv_data;
    MJpegContext * const m = s->mjpeg_ctx;
    AVFrame *pict = data;
    const int width= s->width;
    const int height= s->height;
    AVFrame * const p= (AVFrame*)&s->current_picture;
    const int predictor= avctx->prediction_method+1;

    init_put_bits(&s->pb, buf, buf_size);

    *p = *pict;
    p->pict_type= FF_I_TYPE;
    p->key_frame= 1;

    ff_mjpeg_encode_picture_header(s);

    s->header_bits= put_bits_count(&s->pb);

    if(avctx->pix_fmt == PIX_FMT_BGRA){
        int x, y, i;
        const int linesize= p->linesize[0];
        uint16_t (*buffer)[4]= (void *) s->rd_scratchpad;
        int left[3], top[3], topleft[3];

        for(i=0; i<3; i++){
            buffer[0][i]= 1 << (9 - 1);
        }

        for(y = 0; y < height; y++) {
            const int modified_predictor= y ? predictor : 1;
            uint8_t *ptr = p->data[0] + (linesize * y);

            if(s->pb.buf_end - s->pb.buf - (put_bits_count(&s->pb)>>3) < width*3*4){
                av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");
                return -1;
            }

            for(i=0; i<3; i++){
                top[i]= left[i]= topleft[i]= buffer[0][i];
            }
            for(x = 0; x < width; x++) {
                buffer[x][1] = ptr[4*x+0] - ptr[4*x+1] + 0x100;
                buffer[x][2] = ptr[4*x+2] - ptr[4*x+1] + 0x100;
                buffer[x][0] = (ptr[4*x+0] + 2*ptr[4*x+1] + ptr[4*x+2])>>2;

                for(i=0;i<3;i++) {
                    int pred, diff;

                    PREDICT(pred, topleft[i], top[i], left[i], modified_predictor);

                    topleft[i]= top[i];
                    top[i]= buffer[x+1][i];

                    left[i]= buffer[x][i];

                    diff= ((left[i] - pred + 0x100)&0x1FF) - 0x100;

                    if(i==0)
                        ff_mjpeg_encode_dc(s, diff, m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly
                    else
                        ff_mjpeg_encode_dc(s, diff, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
                }
            }
        }
    }else{
        int mb_x, mb_y, i;
        const int mb_width  = (width  + s->mjpeg_hsample[0] - 1) / s->mjpeg_hsample[0];
        const int mb_height = (height + s->mjpeg_vsample[0] - 1) / s->mjpeg_vsample[0];

        for(mb_y = 0; mb_y < mb_height; mb_y++) {
            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]){
                av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");
                return -1;
            }
            for(mb_x = 0; mb_x < mb_width; mb_x++) {
                if(mb_x==0 || mb_y==0){
                    for(i=0;i<3;i++) {
                        uint8_t *ptr;
                        int x, y, h, v, linesize;
                        h = s->mjpeg_hsample[i];
                        v = s->mjpeg_vsample[i];
                        linesize= p->linesize[i];

                        for(y=0; y<v; y++){
                            for(x=0; x<h; x++){
                                int pred;

                                ptr = p->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
                                if(y==0 && mb_y==0){
                                    if(x==0 && mb_x==0){
                                        pred= 128;
                                    }else{
                                        pred= ptr[-1];
                                    }
                                }else{
                                    if(x==0 && mb_x==0){
                                        pred= ptr[-linesize];
                                    }else{
                                        PREDICT(pred, ptr[-linesize-1], ptr[-linesize], ptr[-1], predictor);
                                    }
                                }

                                if(i==0)
                                    ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly
                                else
                                    ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
                            }
                        }
                    }
                }else{
                    for(i=0;i<3;i++) {
                        uint8_t *ptr;
                        int x, y, h, v, linesize;
                        h = s->mjpeg_hsample[i];
                        v = s->mjpeg_vsample[i];
                        linesize= p->linesize[i];

                        for(y=0; y<v; y++){
                            for(x=0; x<h; x++){
                                int pred;

                                ptr = p->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
//printf("%d %d %d %d %8X\n", mb_x, mb_y, x, y, ptr);
                                PREDICT(pred, ptr[-linesize-1], ptr[-linesize], ptr[-1], predictor);

                                if(i==0)
                                    ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly
                                else
                                    ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
                            }
                        }
                    }
                }
            }
        }
    }

    emms_c();

    ff_mjpeg_encode_picture_trailer(s);
    s->picture_number++;

    flush_put_bits(&s->pb);
    return put_bits_ptr(&s->pb) - s->pb.buf;
//    return (put_bits_count(&f->pb)+7)/8;
}


AVCodec ff_ljpeg_encoder = { //FIXME avoid MPV_* lossless JPEG should not need them
    "ljpeg",
    AVMEDIA_TYPE_VIDEO,
    CODEC_ID_LJPEG,
    sizeof(MpegEncContext),
    MPV_encode_init,
    encode_picture_lossless,
    MPV_encode_end,
    .long_name = NULL_IF_CONFIG_SMALL("Lossless JPEG"),
};