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1 6cea494e Zdenek Kabelac
/*
2
 * Animated GIF encoder
3 19720f15 Fabrice Bellard
 * Copyright (c) 2000 Fabrice Bellard.
4 6cea494e Zdenek Kabelac
 *
5 19720f15 Fabrice Bellard
 * This library is free software; you can redistribute it and/or
6
 * modify it under the terms of the GNU Lesser General Public
7
 * License as published by the Free Software Foundation; either
8
 * version 2 of the License, or (at your option) any later version.
9 6cea494e Zdenek Kabelac
 *
10 19720f15 Fabrice Bellard
 * This library is distributed in the hope that it will be useful,
11 6cea494e Zdenek Kabelac
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 19720f15 Fabrice Bellard
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13
 * Lesser General Public License for more details.
14 6cea494e Zdenek Kabelac
 *
15 19720f15 Fabrice Bellard
 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18 6cea494e Zdenek Kabelac
 */
19
20
/*
21
 * First version by Francois Revol revol@free.fr
22
 *
23
 * Features and limitations:
24
 * - currently no compression is performed,
25
 *   in fact the size of the data is 9/8 the size of the image in 8bpp
26
 * - uses only a global standard palette
27
 * - tested with IE 5.0, Opera for BeOS, NetPositive (BeOS), and Mozilla (BeOS).
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 *
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 * Reference documents:
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 * http://www.goice.co.jp/member/mo/formats/gif.html
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 * http://astronomy.swin.edu.au/pbourke/dataformats/gif/
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 * http://www.dcs.ed.ac.uk/home/mxr/gfx/2d/GIF89a.txt
33
 *
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 * this url claims to have an LZW algorithm not covered by Unisys patent:
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 * http://www.msg.net/utility/whirlgif/gifencod.html
36
 * could help reduce the size of the files _a lot_...
37
 * some sites mentions an RLE type compression also.
38
 */
39
40
#include "avformat.h"
41 2de7795a Michael Niedermayer
#include "bitstream.h"
42 6cea494e Zdenek Kabelac
43
/* bitstream minipacket size */
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#define GIF_CHUNKS 100
45
46
/* slows down the decoding (and some browsers doesn't like it) */
47
/* #define GIF_ADD_APP_HEADER */
48
49
typedef struct {
50
    unsigned char r;
51
    unsigned char g;
52
    unsigned char b;
53
} rgb_triplet;
54
55
/* we use the standard 216 color palette */
56
57
/* this script was used to create the palette:
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 * for r in 00 33 66 99 cc ff; do for g in 00 33 66 99 cc ff; do echo -n "    "; for b in 00 33 66 99 cc ff; do 
59
 *   echo -n "{ 0x$r, 0x$g, 0x$b }, "; done; echo ""; done; done
60
 */
61
62 84082497 Zdenek Kabelac
static const rgb_triplet gif_clut[216] = {
63 6cea494e Zdenek Kabelac
    { 0x00, 0x00, 0x00 }, { 0x00, 0x00, 0x33 }, { 0x00, 0x00, 0x66 }, { 0x00, 0x00, 0x99 }, { 0x00, 0x00, 0xcc }, { 0x00, 0x00, 0xff },
64
    { 0x00, 0x33, 0x00 }, { 0x00, 0x33, 0x33 }, { 0x00, 0x33, 0x66 }, { 0x00, 0x33, 0x99 }, { 0x00, 0x33, 0xcc }, { 0x00, 0x33, 0xff },
65
    { 0x00, 0x66, 0x00 }, { 0x00, 0x66, 0x33 }, { 0x00, 0x66, 0x66 }, { 0x00, 0x66, 0x99 }, { 0x00, 0x66, 0xcc }, { 0x00, 0x66, 0xff },
66
    { 0x00, 0x99, 0x00 }, { 0x00, 0x99, 0x33 }, { 0x00, 0x99, 0x66 }, { 0x00, 0x99, 0x99 }, { 0x00, 0x99, 0xcc }, { 0x00, 0x99, 0xff },
67
    { 0x00, 0xcc, 0x00 }, { 0x00, 0xcc, 0x33 }, { 0x00, 0xcc, 0x66 }, { 0x00, 0xcc, 0x99 }, { 0x00, 0xcc, 0xcc }, { 0x00, 0xcc, 0xff },
68
    { 0x00, 0xff, 0x00 }, { 0x00, 0xff, 0x33 }, { 0x00, 0xff, 0x66 }, { 0x00, 0xff, 0x99 }, { 0x00, 0xff, 0xcc }, { 0x00, 0xff, 0xff },
69
    { 0x33, 0x00, 0x00 }, { 0x33, 0x00, 0x33 }, { 0x33, 0x00, 0x66 }, { 0x33, 0x00, 0x99 }, { 0x33, 0x00, 0xcc }, { 0x33, 0x00, 0xff },
70
    { 0x33, 0x33, 0x00 }, { 0x33, 0x33, 0x33 }, { 0x33, 0x33, 0x66 }, { 0x33, 0x33, 0x99 }, { 0x33, 0x33, 0xcc }, { 0x33, 0x33, 0xff },
71
    { 0x33, 0x66, 0x00 }, { 0x33, 0x66, 0x33 }, { 0x33, 0x66, 0x66 }, { 0x33, 0x66, 0x99 }, { 0x33, 0x66, 0xcc }, { 0x33, 0x66, 0xff },
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    { 0x33, 0x99, 0x00 }, { 0x33, 0x99, 0x33 }, { 0x33, 0x99, 0x66 }, { 0x33, 0x99, 0x99 }, { 0x33, 0x99, 0xcc }, { 0x33, 0x99, 0xff },
73
    { 0x33, 0xcc, 0x00 }, { 0x33, 0xcc, 0x33 }, { 0x33, 0xcc, 0x66 }, { 0x33, 0xcc, 0x99 }, { 0x33, 0xcc, 0xcc }, { 0x33, 0xcc, 0xff },
74
    { 0x33, 0xff, 0x00 }, { 0x33, 0xff, 0x33 }, { 0x33, 0xff, 0x66 }, { 0x33, 0xff, 0x99 }, { 0x33, 0xff, 0xcc }, { 0x33, 0xff, 0xff },
75
    { 0x66, 0x00, 0x00 }, { 0x66, 0x00, 0x33 }, { 0x66, 0x00, 0x66 }, { 0x66, 0x00, 0x99 }, { 0x66, 0x00, 0xcc }, { 0x66, 0x00, 0xff },
76
    { 0x66, 0x33, 0x00 }, { 0x66, 0x33, 0x33 }, { 0x66, 0x33, 0x66 }, { 0x66, 0x33, 0x99 }, { 0x66, 0x33, 0xcc }, { 0x66, 0x33, 0xff },
77
    { 0x66, 0x66, 0x00 }, { 0x66, 0x66, 0x33 }, { 0x66, 0x66, 0x66 }, { 0x66, 0x66, 0x99 }, { 0x66, 0x66, 0xcc }, { 0x66, 0x66, 0xff },
78
    { 0x66, 0x99, 0x00 }, { 0x66, 0x99, 0x33 }, { 0x66, 0x99, 0x66 }, { 0x66, 0x99, 0x99 }, { 0x66, 0x99, 0xcc }, { 0x66, 0x99, 0xff },
79
    { 0x66, 0xcc, 0x00 }, { 0x66, 0xcc, 0x33 }, { 0x66, 0xcc, 0x66 }, { 0x66, 0xcc, 0x99 }, { 0x66, 0xcc, 0xcc }, { 0x66, 0xcc, 0xff },
80
    { 0x66, 0xff, 0x00 }, { 0x66, 0xff, 0x33 }, { 0x66, 0xff, 0x66 }, { 0x66, 0xff, 0x99 }, { 0x66, 0xff, 0xcc }, { 0x66, 0xff, 0xff },
81
    { 0x99, 0x00, 0x00 }, { 0x99, 0x00, 0x33 }, { 0x99, 0x00, 0x66 }, { 0x99, 0x00, 0x99 }, { 0x99, 0x00, 0xcc }, { 0x99, 0x00, 0xff },
82
    { 0x99, 0x33, 0x00 }, { 0x99, 0x33, 0x33 }, { 0x99, 0x33, 0x66 }, { 0x99, 0x33, 0x99 }, { 0x99, 0x33, 0xcc }, { 0x99, 0x33, 0xff },
83
    { 0x99, 0x66, 0x00 }, { 0x99, 0x66, 0x33 }, { 0x99, 0x66, 0x66 }, { 0x99, 0x66, 0x99 }, { 0x99, 0x66, 0xcc }, { 0x99, 0x66, 0xff },
84
    { 0x99, 0x99, 0x00 }, { 0x99, 0x99, 0x33 }, { 0x99, 0x99, 0x66 }, { 0x99, 0x99, 0x99 }, { 0x99, 0x99, 0xcc }, { 0x99, 0x99, 0xff },
85
    { 0x99, 0xcc, 0x00 }, { 0x99, 0xcc, 0x33 }, { 0x99, 0xcc, 0x66 }, { 0x99, 0xcc, 0x99 }, { 0x99, 0xcc, 0xcc }, { 0x99, 0xcc, 0xff },
86
    { 0x99, 0xff, 0x00 }, { 0x99, 0xff, 0x33 }, { 0x99, 0xff, 0x66 }, { 0x99, 0xff, 0x99 }, { 0x99, 0xff, 0xcc }, { 0x99, 0xff, 0xff },
87
    { 0xcc, 0x00, 0x00 }, { 0xcc, 0x00, 0x33 }, { 0xcc, 0x00, 0x66 }, { 0xcc, 0x00, 0x99 }, { 0xcc, 0x00, 0xcc }, { 0xcc, 0x00, 0xff },
88
    { 0xcc, 0x33, 0x00 }, { 0xcc, 0x33, 0x33 }, { 0xcc, 0x33, 0x66 }, { 0xcc, 0x33, 0x99 }, { 0xcc, 0x33, 0xcc }, { 0xcc, 0x33, 0xff },
89
    { 0xcc, 0x66, 0x00 }, { 0xcc, 0x66, 0x33 }, { 0xcc, 0x66, 0x66 }, { 0xcc, 0x66, 0x99 }, { 0xcc, 0x66, 0xcc }, { 0xcc, 0x66, 0xff },
90
    { 0xcc, 0x99, 0x00 }, { 0xcc, 0x99, 0x33 }, { 0xcc, 0x99, 0x66 }, { 0xcc, 0x99, 0x99 }, { 0xcc, 0x99, 0xcc }, { 0xcc, 0x99, 0xff },
91
    { 0xcc, 0xcc, 0x00 }, { 0xcc, 0xcc, 0x33 }, { 0xcc, 0xcc, 0x66 }, { 0xcc, 0xcc, 0x99 }, { 0xcc, 0xcc, 0xcc }, { 0xcc, 0xcc, 0xff },
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    { 0xcc, 0xff, 0x00 }, { 0xcc, 0xff, 0x33 }, { 0xcc, 0xff, 0x66 }, { 0xcc, 0xff, 0x99 }, { 0xcc, 0xff, 0xcc }, { 0xcc, 0xff, 0xff },
93
    { 0xff, 0x00, 0x00 }, { 0xff, 0x00, 0x33 }, { 0xff, 0x00, 0x66 }, { 0xff, 0x00, 0x99 }, { 0xff, 0x00, 0xcc }, { 0xff, 0x00, 0xff },
94
    { 0xff, 0x33, 0x00 }, { 0xff, 0x33, 0x33 }, { 0xff, 0x33, 0x66 }, { 0xff, 0x33, 0x99 }, { 0xff, 0x33, 0xcc }, { 0xff, 0x33, 0xff },
95
    { 0xff, 0x66, 0x00 }, { 0xff, 0x66, 0x33 }, { 0xff, 0x66, 0x66 }, { 0xff, 0x66, 0x99 }, { 0xff, 0x66, 0xcc }, { 0xff, 0x66, 0xff },
96
    { 0xff, 0x99, 0x00 }, { 0xff, 0x99, 0x33 }, { 0xff, 0x99, 0x66 }, { 0xff, 0x99, 0x99 }, { 0xff, 0x99, 0xcc }, { 0xff, 0x99, 0xff },
97
    { 0xff, 0xcc, 0x00 }, { 0xff, 0xcc, 0x33 }, { 0xff, 0xcc, 0x66 }, { 0xff, 0xcc, 0x99 }, { 0xff, 0xcc, 0xcc }, { 0xff, 0xcc, 0xff },
98
    { 0xff, 0xff, 0x00 }, { 0xff, 0xff, 0x33 }, { 0xff, 0xff, 0x66 }, { 0xff, 0xff, 0x99 }, { 0xff, 0xff, 0xcc }, { 0xff, 0xff, 0xff },
99
};
100
101
/* The GIF format uses reversed order for bitstreams... */
102
/* at least they don't use PDP_ENDIAN :) */
103
/* so we 'extend' PutBitContext. hmmm, OOP :) */
104
/* seems this thing changed slightly since I wrote it... */
105
106
#ifdef ALT_BITSTREAM_WRITER
107
# error no ALT_BITSTREAM_WRITER support for now
108
#endif
109
110 84082497 Zdenek Kabelac
static void gif_put_bits_rev(PutBitContext *s, int n, unsigned int value)
111 6cea494e Zdenek Kabelac
{
112
    unsigned int bit_buf;
113
    int bit_cnt;
114
115
#ifdef STATS
116
    st_out_bit_counts[st_current_index] += n;
117
#endif
118
    //    printf("put_bits=%d %x\n", n, value);
119
    assert(n == 32 || value < (1U << n));
120
121
    bit_buf = s->bit_buf;
122
    bit_cnt = 32 - s->bit_left; /* XXX:lazyness... was = s->bit_cnt; */
123
124
    //    printf("n=%d value=%x cnt=%d buf=%x\n", n, value, bit_cnt, bit_buf);
125
    /* XXX: optimize */
126
    if (n < (32-bit_cnt)) {
127
        bit_buf |= value << (bit_cnt);
128
        bit_cnt+=n;
129
    } else {
130
        bit_buf |= value << (bit_cnt);
131
        
132
        *s->buf_ptr = bit_buf & 0xff;
133
        s->buf_ptr[1] = (bit_buf >> 8) & 0xff;
134
        s->buf_ptr[2] = (bit_buf >> 16) & 0xff;
135
        s->buf_ptr[3] = (bit_buf >> 24) & 0xff;
136
        
137
        //printf("bitbuf = %08x\n", bit_buf);
138
        s->buf_ptr+=4;
139
        if (s->buf_ptr >= s->buf_end)
140
            puts("bit buffer overflow !!"); // should never happen ! who got rid of the callback ???
141
//            flush_buffer_rev(s);
142
        bit_cnt=bit_cnt + n - 32;
143
        if (bit_cnt == 0) {
144
            bit_buf = 0;
145
        } else {
146
            bit_buf = value >> (n - bit_cnt);
147
        }
148
    }
149
150
    s->bit_buf = bit_buf;
151
    s->bit_left = 32 - bit_cnt;
152
}
153
154
/* pad the end of the output stream with zeros */
155 84082497 Zdenek Kabelac
static void gif_flush_put_bits_rev(PutBitContext *s)
156 6cea494e Zdenek Kabelac
{
157
    while (s->bit_left < 32) {
158
        /* XXX: should test end of buffer */
159
        *s->buf_ptr++=s->bit_buf & 0xff;
160
        s->bit_buf>>=8;
161
        s->bit_left+=8;
162
    }
163
//    flush_buffer_rev(s);
164
    s->bit_left=32;
165
    s->bit_buf=0;
166
}
167
168
/* !RevPutBitContext */
169
170 ba19f848 Fabrice Bellard
/* GIF header */
171 84ab361f Fabrice Bellard
static int gif_image_write_header(ByteIOContext *pb, 
172
                                  int width, int height, uint32_t *palette)
173 6cea494e Zdenek Kabelac
{
174 ba19f848 Fabrice Bellard
    int i;
175 84ab361f Fabrice Bellard
    unsigned int v;
176 6cea494e Zdenek Kabelac
177
    put_tag(pb, "GIF");
178
    put_tag(pb, "89a");
179
    put_le16(pb, width);
180
    put_le16(pb, height);
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182
    put_byte(pb, 0xf7); /* flags: global clut, 256 entries */
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    put_byte(pb, 0x1f); /* background color index */
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    put_byte(pb, 0); /* aspect ratio */
185
186
    /* the global palette */
187 84ab361f Fabrice Bellard
    if (!palette) {
188
        put_buffer(pb, (unsigned char *)gif_clut, 216*3);
189
        for(i=0;i<((256-216)*3);i++)
190
            put_byte(pb, 0);
191
    } else {
192
        for(i=0;i<256;i++) {
193
            v = palette[i];
194
            put_byte(pb, (v >> 16) & 0xff);
195
            put_byte(pb, (v >> 8) & 0xff);
196
            put_byte(pb, (v) & 0xff);
197
        }
198
    }
199 6cea494e Zdenek Kabelac
200
    /* application extension header */
201
    /* XXX: not really sure what to put in here... */
202
#ifdef GIF_ADD_APP_HEADER
203
    put_byte(pb, 0x21);
204
    put_byte(pb, 0xff);
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    put_byte(pb, 0x0b);
206
    put_tag(pb, "NETSCAPE2.0");
207
    put_byte(pb, 0x03);
208
    put_byte(pb, 0x01);
209
    put_byte(pb, 0x00);
210
    put_byte(pb, 0x00);
211
#endif
212
    return 0;
213
}
214
215
/* this is maybe slow, but allows for extensions */
216 0c1a9eda Zdenek Kabelac
static inline unsigned char gif_clut_index(uint8_t r, uint8_t g, uint8_t b)
217 6cea494e Zdenek Kabelac
{
218
    return ((((r)/47)%6)*6*6+(((g)/47)%6)*6+(((b)/47)%6));
219
}
220
221
222 ba19f848 Fabrice Bellard
static int gif_image_write_image(ByteIOContext *pb, 
223
                                 int x1, int y1, int width, int height,
224 49057904 Fabrice Bellard
                                 const uint8_t *buf, int linesize, int pix_fmt)
225 6cea494e Zdenek Kabelac
{
226
    PutBitContext p;
227 0c1a9eda Zdenek Kabelac
    uint8_t buffer[200]; /* 100 * 9 / 8 = 113 */
228 84ab361f Fabrice Bellard
    int i, left, w, v;
229 49057904 Fabrice Bellard
    const uint8_t *ptr;
230 6cea494e Zdenek Kabelac
    /* image block */
231
232
    put_byte(pb, 0x2c);
233 ba19f848 Fabrice Bellard
    put_le16(pb, x1);
234
    put_le16(pb, y1);
235
    put_le16(pb, width);
236
    put_le16(pb, height);
237 6cea494e Zdenek Kabelac
    put_byte(pb, 0x00); /* flags */
238
    /* no local clut */
239
240
    put_byte(pb, 0x08);
241
242 ba19f848 Fabrice Bellard
    left= width * height;
243 6cea494e Zdenek Kabelac
244 117a5490 Alex Beregszaszi
    init_put_bits(&p, buffer, 130);
245 6cea494e Zdenek Kabelac
246
/*
247
 * the thing here is the bitstream is written as little packets, with a size byte before
248
 * but it's still the same bitstream between packets (no flush !)
249
 */
250 ba19f848 Fabrice Bellard
    ptr = buf;
251
    w = width;
252 6cea494e Zdenek Kabelac
    while(left>0) {
253
254 84082497 Zdenek Kabelac
        gif_put_bits_rev(&p, 9, 0x0100); /* clear code */
255 6cea494e Zdenek Kabelac
256 f5fc28d2 Roman Shaposhnik
        for(i=(left<GIF_CHUNKS)?left:GIF_CHUNKS;i;i--) {
257 84ab361f Fabrice Bellard
            if (pix_fmt == PIX_FMT_RGB24) {
258
                v = gif_clut_index(ptr[0], ptr[1], ptr[2]);
259
                ptr+=3;
260
            } else {
261
                v = *ptr++;
262
            }
263
            gif_put_bits_rev(&p, 9, v);
264 ba19f848 Fabrice Bellard
            if (--w == 0) {
265
                w = width;
266
                buf += linesize;
267
                ptr = buf;
268
            }
269 6cea494e Zdenek Kabelac
        }
270
271
        if(left<=GIF_CHUNKS) {
272 84082497 Zdenek Kabelac
            gif_put_bits_rev(&p, 9, 0x101); /* end of stream */
273
            gif_flush_put_bits_rev(&p);
274 6cea494e Zdenek Kabelac
        }
275
        if(pbBufPtr(&p) - p.buf > 0) {
276
            put_byte(pb, pbBufPtr(&p) - p.buf); /* byte count of the packet */
277
            put_buffer(pb, p.buf, pbBufPtr(&p) - p.buf); /* the actual buffer */
278
            p.buf_ptr = p.buf; /* dequeue the bytes off the bitstream */
279
        }
280
        left-=GIF_CHUNKS;
281
    }
282 f5fc28d2 Roman Shaposhnik
    put_byte(pb, 0x00); /* end of image block */
283
    
284 ba19f848 Fabrice Bellard
    return 0;
285
}
286
287
typedef struct {
288 0c1a9eda Zdenek Kabelac
    int64_t time, file_time;
289
    uint8_t buffer[100]; /* data chunks */
290 ba19f848 Fabrice Bellard
} GIFContext;
291
292
static int gif_write_header(AVFormatContext *s)
293
{
294
    GIFContext *gif = s->priv_data;
295
    ByteIOContext *pb = &s->pb;
296
    AVCodecContext *enc, *video_enc;
297 14bea432 Michael Niedermayer
    int i, width, height/*, rate*/;
298 ba19f848 Fabrice Bellard
299
/* XXX: do we reject audio streams or just ignore them ?
300
    if(s->nb_streams > 1)
301
        return -1;
302
*/
303
    gif->time = 0;
304
    gif->file_time = 0;
305
306
    video_enc = NULL;
307
    for(i=0;i<s->nb_streams;i++) {
308
        enc = &s->streams[i]->codec;
309
        if (enc->codec_type != CODEC_TYPE_AUDIO)
310
            video_enc = enc;
311
    }
312
313
    if (!video_enc) {
314
        av_free(gif);
315
        return -1;
316
    } else {
317
        width = video_enc->width;
318
        height = video_enc->height;
319 c0df9d75 Michael Niedermayer
//        rate = video_enc->time_base.den;
320 ba19f848 Fabrice Bellard
    }
321
322
    /* XXX: is it allowed ? seems to work so far... */
323
    video_enc->pix_fmt = PIX_FMT_RGB24;
324
325 84ab361f Fabrice Bellard
    gif_image_write_header(pb, width, height, NULL);
326 ba19f848 Fabrice Bellard
327
    put_flush_packet(&s->pb);
328
    return 0;
329
}
330
331
static int gif_write_video(AVFormatContext *s, 
332 49057904 Fabrice Bellard
                           AVCodecContext *enc, const uint8_t *buf, int size)
333 ba19f848 Fabrice Bellard
{
334
    ByteIOContext *pb = &s->pb;
335
    GIFContext *gif = s->priv_data;
336
    int jiffies;
337 0c1a9eda Zdenek Kabelac
    int64_t delay;
338 ba19f848 Fabrice Bellard
339
    /* graphic control extension block */
340
    put_byte(pb, 0x21);
341
    put_byte(pb, 0xf9);
342
    put_byte(pb, 0x04); /* block size */
343
    put_byte(pb, 0x04); /* flags */
344
    
345
    /* 1 jiffy is 1/70 s */
346
    /* the delay_time field indicates the number of jiffies - 1 */
347
    delay = gif->file_time - gif->time;
348
349
    /* XXX: should use delay, in order to be more accurate */
350
    /* instead of using the same rounded value each time */
351
    /* XXX: don't even remember if I really use it for now */
352 c0df9d75 Michael Niedermayer
    jiffies = (70*enc->time_base.num/enc->time_base.den) - 1;
353 ba19f848 Fabrice Bellard
354
    put_le16(pb, jiffies);
355
356
    put_byte(pb, 0x1f); /* transparent color index */
357
    put_byte(pb, 0x00);
358
359
    gif_image_write_image(pb, 0, 0, enc->width, enc->height,
360 84ab361f Fabrice Bellard
                          buf, enc->width * 3, PIX_FMT_RGB24);
361 6cea494e Zdenek Kabelac
362
    put_flush_packet(&s->pb);
363
    return 0;
364
}
365
366 e928649b Michael Niedermayer
static int gif_write_packet(AVFormatContext *s, AVPacket *pkt)
367 6cea494e Zdenek Kabelac
{
368 e928649b Michael Niedermayer
    AVCodecContext *codec = &s->streams[pkt->stream_index]->codec;
369 6cea494e Zdenek Kabelac
    if (codec->codec_type == CODEC_TYPE_AUDIO)
370
        return 0; /* just ignore audio */
371
    else
372 e928649b Michael Niedermayer
        return gif_write_video(s, codec, pkt->data, pkt->size);
373 6cea494e Zdenek Kabelac
}
374
375
static int gif_write_trailer(AVFormatContext *s)
376
{
377
    ByteIOContext *pb = &s->pb;
378
379
    put_byte(pb, 0x3b);
380
    put_flush_packet(&s->pb);
381
    return 0;
382
}
383
384 ba19f848 Fabrice Bellard
/* better than nothing gif image writer */
385
int gif_write(ByteIOContext *pb, AVImageInfo *info)
386
{
387 84ab361f Fabrice Bellard
    gif_image_write_header(pb, info->width, info->height, 
388
                           (uint32_t *)info->pict.data[1]);
389 ba19f848 Fabrice Bellard
    gif_image_write_image(pb, 0, 0, info->width, info->height, 
390 84ab361f Fabrice Bellard
                          info->pict.data[0], info->pict.linesize[0], 
391
                          PIX_FMT_PAL8);
392 ba19f848 Fabrice Bellard
    put_byte(pb, 0x3b);
393
    put_flush_packet(pb);
394
    return 0;
395
}
396
397 c9a65ca8 Fabrice Bellard
static AVOutputFormat gif_oformat = {
398 6cea494e Zdenek Kabelac
    "gif",
399
    "GIF Animation",
400
    "image/gif",
401
    "gif",
402 c9a65ca8 Fabrice Bellard
    sizeof(GIFContext),
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    CODEC_ID_NONE,
404
    CODEC_ID_RAWVIDEO,
405
    gif_write_header,
406
    gif_write_packet,
407
    gif_write_trailer,
408
};
409 ba19f848 Fabrice Bellard
410 12b64a22 Fabrice Bellard
extern AVInputFormat gif_iformat;
411 c9a65ca8 Fabrice Bellard
412
int gif_init(void)
413
{
414
    av_register_output_format(&gif_oformat);
415 12b64a22 Fabrice Bellard
    av_register_input_format(&gif_iformat);
416 c9a65ca8 Fabrice Bellard
    return 0;
417
}