summaryrefslogtreecommitdiffstats
path: root/libavcodec/sgienc.c
blob: f4d651e6bb6a3ff758fda7fbf279b5e95ec60863 (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
/*
 * SGI image encoder
 * Todd Kirby <doubleshot@pacbell.net>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg 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.
 *
 * FFmpeg 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 FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "avcodec.h"
#include "bytestream.h"
#include "sgi.h"
#include "rle.h"

#define SGI_SINGLE_CHAN 2
#define SGI_MULTI_CHAN 3

typedef struct SgiContext {
    AVFrame picture;
} SgiContext;

static av_cold int encode_init(AVCodecContext *avctx){
    SgiContext *s = avctx->priv_data;

    avcodec_get_frame_defaults(&s->picture);
    avctx->coded_frame = &s->picture;

    return 0;
}

static int encode_frame(AVCodecContext *avctx, unsigned char *buf,
                        int buf_size, void *data) {
    SgiContext *s = avctx->priv_data;
    AVFrame * const p = &s->picture;
    uint8_t *offsettab, *lengthtab, *in_buf, *encode_buf;
    int x, y, z, length, tablesize;
    unsigned int width, height, depth, dimension;
    unsigned char *orig_buf = buf, *end_buf = buf + buf_size;

    *p = *(AVFrame*)data;
    p->pict_type = FF_I_TYPE;
    p->key_frame = 1;

    width = avctx->width;
    height = avctx->height;

    switch (avctx->pix_fmt) {
        case PIX_FMT_GRAY8:
            dimension = SGI_SINGLE_CHAN;
            depth = SGI_GRAYSCALE;
            break;
        case PIX_FMT_RGB24:
            dimension = SGI_MULTI_CHAN;
            depth = SGI_RGB;
            break;
        case PIX_FMT_RGBA:
            dimension = SGI_MULTI_CHAN;
            depth = SGI_RGBA;
            break;
        default:
            return AVERROR_INVALIDDATA;
    }

    tablesize = depth * height * 4;
    length = tablesize * 2 + SGI_HEADER_SIZE;

    if (buf_size < length) {
        av_log(avctx, AV_LOG_ERROR, "buf_size too small(need %d, got %d)\n", length, buf_size);
        return -1;
    }

    /* Encode header. */
    bytestream_put_be16(&buf, SGI_MAGIC);
    bytestream_put_byte(&buf, 1); /* RLE */
    bytestream_put_byte(&buf, 1); /* bytes_per_channel */
    bytestream_put_be16(&buf, dimension);
    bytestream_put_be16(&buf, width);
    bytestream_put_be16(&buf, height);
    bytestream_put_be16(&buf, depth);

    /* The rest are constant in this implementation. */
    bytestream_put_be32(&buf, 0L); /* pixmin */
    bytestream_put_be32(&buf, 255L); /* pixmax */
    bytestream_put_be32(&buf, 0L); /* dummy */

    /* name */
    memset(buf, 0, SGI_HEADER_SIZE);
    buf += 80;

     /* colormap */
    bytestream_put_be32(&buf, 0L);

    /* The rest of the 512 byte header is unused. */
    buf += 404;
    offsettab = buf;

    /* Skip RLE offset table. */
    buf += tablesize;
    lengthtab = buf;

    /* Skip RLE length table. */
    buf += tablesize;

    /* Make an intermediate consecutive buffer. */
    if ((encode_buf = av_malloc(width)) == NULL)
        return -1;

    for (z = 0; z < depth; z++) {
        in_buf = p->data[0] + p->linesize[0] * (height - 1) + z;

        for (y = 0; y < height; y++) {
            bytestream_put_be32(&offsettab, buf - orig_buf);

            for (x = 0; x < width; x++)
                encode_buf[x] = in_buf[depth * x];

            if((length = ff_rle_encode(buf, end_buf - buf - 1, encode_buf, 1, width, 0, 0, 0x80, 0)) < 1) {
                av_free(encode_buf);
                return -1;
            }

            buf += length;
            bytestream_put_byte(&buf, 0);
            bytestream_put_be32(&lengthtab, length + 1);
            in_buf -= p->linesize[0];
        }
    }

    av_free(encode_buf);
    /* total length */
    return buf - orig_buf;
}

AVCodec sgi_encoder = {
    "sgi",
    CODEC_TYPE_VIDEO,
    CODEC_ID_SGI,
    sizeof(SgiContext),
    encode_init,
    encode_frame,
    NULL,
    .pix_fmts= (enum PixelFormat[]){PIX_FMT_RGB24, PIX_FMT_RGBA, PIX_FMT_PAL8, PIX_FMT_GRAY8, PIX_FMT_NONE},
    .long_name= NULL_IF_CONFIG_SMALL("SGI image"),
};

OpenPOWER on IntegriCloud