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1 6cea494e Zdenek Kabelac
/*
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 * 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
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 * License as published by the Free Software Foundation; either
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 * 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
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 * 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
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 *
23
 * Features and limitations:
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 * - currently no compression is performed,
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 *   in fact the size of the data is 9/8 the size of the image in 8bpp
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 * - uses only a global standard palette
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 * - 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
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 *
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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
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 * could help reduce the size of the files _a lot_...
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 * some sites mentions an RLE type compression also.
38
 */
39
40
#include "avformat.h"
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/* bitstream minipacket size */
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#define GIF_CHUNKS 100
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45
/* slows down the decoding (and some browsers doesn't like it) */
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/* #define GIF_ADD_APP_HEADER */
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typedef struct {
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    unsigned char r;
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    unsigned char g;
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    unsigned char b;
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} rgb_triplet;
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/* we use the standard 216 color palette */
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56
/* 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 
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 *   echo -n "{ 0x$r, 0x$g, 0x$b }, "; done; echo ""; done; done
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 */
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61 84082497 Zdenek Kabelac
static const rgb_triplet gif_clut[216] = {
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    { 0x00, 0x00, 0x00 }, { 0x00, 0x00, 0x33 }, { 0x00, 0x00, 0x66 }, { 0x00, 0x00, 0x99 }, { 0x00, 0x00, 0xcc }, { 0x00, 0x00, 0xff },
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    { 0x00, 0x33, 0x00 }, { 0x00, 0x33, 0x33 }, { 0x00, 0x33, 0x66 }, { 0x00, 0x33, 0x99 }, { 0x00, 0x33, 0xcc }, { 0x00, 0x33, 0xff },
64
    { 0x00, 0x66, 0x00 }, { 0x00, 0x66, 0x33 }, { 0x00, 0x66, 0x66 }, { 0x00, 0x66, 0x99 }, { 0x00, 0x66, 0xcc }, { 0x00, 0x66, 0xff },
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    { 0x00, 0x99, 0x00 }, { 0x00, 0x99, 0x33 }, { 0x00, 0x99, 0x66 }, { 0x00, 0x99, 0x99 }, { 0x00, 0x99, 0xcc }, { 0x00, 0x99, 0xff },
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    { 0x00, 0xcc, 0x00 }, { 0x00, 0xcc, 0x33 }, { 0x00, 0xcc, 0x66 }, { 0x00, 0xcc, 0x99 }, { 0x00, 0xcc, 0xcc }, { 0x00, 0xcc, 0xff },
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    { 0x00, 0xff, 0x00 }, { 0x00, 0xff, 0x33 }, { 0x00, 0xff, 0x66 }, { 0x00, 0xff, 0x99 }, { 0x00, 0xff, 0xcc }, { 0x00, 0xff, 0xff },
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    { 0x33, 0x00, 0x00 }, { 0x33, 0x00, 0x33 }, { 0x33, 0x00, 0x66 }, { 0x33, 0x00, 0x99 }, { 0x33, 0x00, 0xcc }, { 0x33, 0x00, 0xff },
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    { 0x33, 0x33, 0x00 }, { 0x33, 0x33, 0x33 }, { 0x33, 0x33, 0x66 }, { 0x33, 0x33, 0x99 }, { 0x33, 0x33, 0xcc }, { 0x33, 0x33, 0xff },
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    { 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 },
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    { 0x33, 0xcc, 0x00 }, { 0x33, 0xcc, 0x33 }, { 0x33, 0xcc, 0x66 }, { 0x33, 0xcc, 0x99 }, { 0x33, 0xcc, 0xcc }, { 0x33, 0xcc, 0xff },
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    { 0x33, 0xff, 0x00 }, { 0x33, 0xff, 0x33 }, { 0x33, 0xff, 0x66 }, { 0x33, 0xff, 0x99 }, { 0x33, 0xff, 0xcc }, { 0x33, 0xff, 0xff },
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    { 0x66, 0x00, 0x00 }, { 0x66, 0x00, 0x33 }, { 0x66, 0x00, 0x66 }, { 0x66, 0x00, 0x99 }, { 0x66, 0x00, 0xcc }, { 0x66, 0x00, 0xff },
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    { 0x66, 0x33, 0x00 }, { 0x66, 0x33, 0x33 }, { 0x66, 0x33, 0x66 }, { 0x66, 0x33, 0x99 }, { 0x66, 0x33, 0xcc }, { 0x66, 0x33, 0xff },
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    { 0x66, 0x66, 0x00 }, { 0x66, 0x66, 0x33 }, { 0x66, 0x66, 0x66 }, { 0x66, 0x66, 0x99 }, { 0x66, 0x66, 0xcc }, { 0x66, 0x66, 0xff },
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    { 0x66, 0x99, 0x00 }, { 0x66, 0x99, 0x33 }, { 0x66, 0x99, 0x66 }, { 0x66, 0x99, 0x99 }, { 0x66, 0x99, 0xcc }, { 0x66, 0x99, 0xff },
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    { 0x66, 0xcc, 0x00 }, { 0x66, 0xcc, 0x33 }, { 0x66, 0xcc, 0x66 }, { 0x66, 0xcc, 0x99 }, { 0x66, 0xcc, 0xcc }, { 0x66, 0xcc, 0xff },
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    { 0x66, 0xff, 0x00 }, { 0x66, 0xff, 0x33 }, { 0x66, 0xff, 0x66 }, { 0x66, 0xff, 0x99 }, { 0x66, 0xff, 0xcc }, { 0x66, 0xff, 0xff },
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    { 0x99, 0x00, 0x00 }, { 0x99, 0x00, 0x33 }, { 0x99, 0x00, 0x66 }, { 0x99, 0x00, 0x99 }, { 0x99, 0x00, 0xcc }, { 0x99, 0x00, 0xff },
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    { 0x99, 0x33, 0x00 }, { 0x99, 0x33, 0x33 }, { 0x99, 0x33, 0x66 }, { 0x99, 0x33, 0x99 }, { 0x99, 0x33, 0xcc }, { 0x99, 0x33, 0xff },
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    { 0x99, 0x66, 0x00 }, { 0x99, 0x66, 0x33 }, { 0x99, 0x66, 0x66 }, { 0x99, 0x66, 0x99 }, { 0x99, 0x66, 0xcc }, { 0x99, 0x66, 0xff },
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    { 0x99, 0x99, 0x00 }, { 0x99, 0x99, 0x33 }, { 0x99, 0x99, 0x66 }, { 0x99, 0x99, 0x99 }, { 0x99, 0x99, 0xcc }, { 0x99, 0x99, 0xff },
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    { 0x99, 0xcc, 0x00 }, { 0x99, 0xcc, 0x33 }, { 0x99, 0xcc, 0x66 }, { 0x99, 0xcc, 0x99 }, { 0x99, 0xcc, 0xcc }, { 0x99, 0xcc, 0xff },
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    { 0x99, 0xff, 0x00 }, { 0x99, 0xff, 0x33 }, { 0x99, 0xff, 0x66 }, { 0x99, 0xff, 0x99 }, { 0x99, 0xff, 0xcc }, { 0x99, 0xff, 0xff },
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    { 0xcc, 0x00, 0x00 }, { 0xcc, 0x00, 0x33 }, { 0xcc, 0x00, 0x66 }, { 0xcc, 0x00, 0x99 }, { 0xcc, 0x00, 0xcc }, { 0xcc, 0x00, 0xff },
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    { 0xcc, 0x33, 0x00 }, { 0xcc, 0x33, 0x33 }, { 0xcc, 0x33, 0x66 }, { 0xcc, 0x33, 0x99 }, { 0xcc, 0x33, 0xcc }, { 0xcc, 0x33, 0xff },
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    { 0xcc, 0x66, 0x00 }, { 0xcc, 0x66, 0x33 }, { 0xcc, 0x66, 0x66 }, { 0xcc, 0x66, 0x99 }, { 0xcc, 0x66, 0xcc }, { 0xcc, 0x66, 0xff },
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    { 0xcc, 0x99, 0x00 }, { 0xcc, 0x99, 0x33 }, { 0xcc, 0x99, 0x66 }, { 0xcc, 0x99, 0x99 }, { 0xcc, 0x99, 0xcc }, { 0xcc, 0x99, 0xff },
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    { 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 },
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    { 0xff, 0x00, 0x00 }, { 0xff, 0x00, 0x33 }, { 0xff, 0x00, 0x66 }, { 0xff, 0x00, 0x99 }, { 0xff, 0x00, 0xcc }, { 0xff, 0x00, 0xff },
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    { 0xff, 0x33, 0x00 }, { 0xff, 0x33, 0x33 }, { 0xff, 0x33, 0x66 }, { 0xff, 0x33, 0x99 }, { 0xff, 0x33, 0xcc }, { 0xff, 0x33, 0xff },
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    { 0xff, 0x66, 0x00 }, { 0xff, 0x66, 0x33 }, { 0xff, 0x66, 0x66 }, { 0xff, 0x66, 0x99 }, { 0xff, 0x66, 0xcc }, { 0xff, 0x66, 0xff },
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    { 0xff, 0x99, 0x00 }, { 0xff, 0x99, 0x33 }, { 0xff, 0x99, 0x66 }, { 0xff, 0x99, 0x99 }, { 0xff, 0x99, 0xcc }, { 0xff, 0x99, 0xff },
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    { 0xff, 0xcc, 0x00 }, { 0xff, 0xcc, 0x33 }, { 0xff, 0xcc, 0x66 }, { 0xff, 0xcc, 0x99 }, { 0xff, 0xcc, 0xcc }, { 0xff, 0xcc, 0xff },
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    { 0xff, 0xff, 0x00 }, { 0xff, 0xff, 0x33 }, { 0xff, 0xff, 0x66 }, { 0xff, 0xff, 0x99 }, { 0xff, 0xff, 0xcc }, { 0xff, 0xff, 0xff },
98
};
99
100
/* The GIF format uses reversed order for bitstreams... */
101
/* at least they don't use PDP_ENDIAN :) */
102
/* so we 'extend' PutBitContext. hmmm, OOP :) */
103
/* seems this thing changed slightly since I wrote it... */
104
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#ifdef ALT_BITSTREAM_WRITER
106
# error no ALT_BITSTREAM_WRITER support for now
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#endif
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109 84082497 Zdenek Kabelac
static void gif_put_bits_rev(PutBitContext *s, int n, unsigned int value)
110 6cea494e Zdenek Kabelac
{
111
    unsigned int bit_buf;
112
    int bit_cnt;
113
114
#ifdef STATS
115
    st_out_bit_counts[st_current_index] += n;
116
#endif
117
    //    printf("put_bits=%d %x\n", n, value);
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    assert(n == 32 || value < (1U << n));
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    bit_buf = s->bit_buf;
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    bit_cnt = 32 - s->bit_left; /* XXX:lazyness... was = s->bit_cnt; */
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    //    printf("n=%d value=%x cnt=%d buf=%x\n", n, value, bit_cnt, bit_buf);
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    /* XXX: optimize */
125
    if (n < (32-bit_cnt)) {
126
        bit_buf |= value << (bit_cnt);
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        bit_cnt+=n;
128
    } else {
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        bit_buf |= value << (bit_cnt);
130
        
131
        *s->buf_ptr = bit_buf & 0xff;
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        s->buf_ptr[1] = (bit_buf >> 8) & 0xff;
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        s->buf_ptr[2] = (bit_buf >> 16) & 0xff;
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        s->buf_ptr[3] = (bit_buf >> 24) & 0xff;
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        //printf("bitbuf = %08x\n", bit_buf);
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        s->buf_ptr+=4;
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        if (s->buf_ptr >= s->buf_end)
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            puts("bit buffer overflow !!"); // should never happen ! who got rid of the callback ???
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//            flush_buffer_rev(s);
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        bit_cnt=bit_cnt + n - 32;
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        if (bit_cnt == 0) {
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            bit_buf = 0;
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        } else {
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            bit_buf = value >> (n - bit_cnt);
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        }
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    }
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    s->bit_buf = bit_buf;
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    s->bit_left = 32 - bit_cnt;
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}
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/* pad the end of the output stream with zeros */
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static void gif_flush_put_bits_rev(PutBitContext *s)
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{
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    while (s->bit_left < 32) {
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        /* XXX: should test end of buffer */
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        *s->buf_ptr++=s->bit_buf & 0xff;
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        s->bit_buf>>=8;
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        s->bit_left+=8;
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    }
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//    flush_buffer_rev(s);
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    s->bit_left=32;
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    s->bit_buf=0;
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}
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/* !RevPutBitContext */
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169 ba19f848 Fabrice Bellard
/* GIF header */
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static int gif_image_write_header(ByteIOContext *pb, 
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                                  int width, int height, uint32_t *palette)
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{
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    int i;
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    unsigned int v;
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    put_tag(pb, "GIF");
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    put_tag(pb, "89a");
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    put_le16(pb, width);
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    put_le16(pb, height);
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    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 */
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    /* the global palette */
186 84ab361f Fabrice Bellard
    if (!palette) {
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        put_buffer(pb, (unsigned char *)gif_clut, 216*3);
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        for(i=0;i<((256-216)*3);i++)
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            put_byte(pb, 0);
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    } else {
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        for(i=0;i<256;i++) {
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            v = palette[i];
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            put_byte(pb, (v >> 16) & 0xff);
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            put_byte(pb, (v >> 8) & 0xff);
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            put_byte(pb, (v) & 0xff);
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        }
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    }
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    /* application extension header */
200
    /* XXX: not really sure what to put in here... */
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#ifdef GIF_ADD_APP_HEADER
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    put_byte(pb, 0x21);
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    put_byte(pb, 0xff);
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    put_byte(pb, 0x0b);
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    put_tag(pb, "NETSCAPE2.0");
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    put_byte(pb, 0x03);
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    put_byte(pb, 0x01);
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    put_byte(pb, 0x00);
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    put_byte(pb, 0x00);
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#endif
211
    return 0;
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}
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/* this is maybe slow, but allows for extensions */
215 0c1a9eda Zdenek Kabelac
static inline unsigned char gif_clut_index(uint8_t r, uint8_t g, uint8_t b)
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{
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    return ((((r)/47)%6)*6*6+(((g)/47)%6)*6+(((b)/47)%6));
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}
219
220
221 ba19f848 Fabrice Bellard
static int gif_image_write_image(ByteIOContext *pb, 
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                                 int x1, int y1, int width, int height,
223 49057904 Fabrice Bellard
                                 const uint8_t *buf, int linesize, int pix_fmt)
224 6cea494e Zdenek Kabelac
{
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    PutBitContext p;
226 0c1a9eda Zdenek Kabelac
    uint8_t buffer[200]; /* 100 * 9 / 8 = 113 */
227 84ab361f Fabrice Bellard
    int i, left, w, v;
228 49057904 Fabrice Bellard
    const uint8_t *ptr;
229 6cea494e Zdenek Kabelac
    /* image block */
230
231
    put_byte(pb, 0x2c);
232 ba19f848 Fabrice Bellard
    put_le16(pb, x1);
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    put_le16(pb, y1);
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    put_le16(pb, width);
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    put_le16(pb, height);
236 6cea494e Zdenek Kabelac
    put_byte(pb, 0x00); /* flags */
237
    /* no local clut */
238
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    put_byte(pb, 0x08);
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241 ba19f848 Fabrice Bellard
    left= width * height;
242 6cea494e Zdenek Kabelac
243 117a5490 Alex Beregszaszi
    init_put_bits(&p, buffer, 130);
244 6cea494e Zdenek Kabelac
245
/*
246
 * the thing here is the bitstream is written as little packets, with a size byte before
247
 * but it's still the same bitstream between packets (no flush !)
248
 */
249 ba19f848 Fabrice Bellard
    ptr = buf;
250
    w = width;
251 6cea494e Zdenek Kabelac
    while(left>0) {
252
253 84082497 Zdenek Kabelac
        gif_put_bits_rev(&p, 9, 0x0100); /* clear code */
254 6cea494e Zdenek Kabelac
255
        for(i=0;i<GIF_CHUNKS;i++) {
256 84ab361f Fabrice Bellard
            if (pix_fmt == PIX_FMT_RGB24) {
257
                v = gif_clut_index(ptr[0], ptr[1], ptr[2]);
258
                ptr+=3;
259
            } else {
260
                v = *ptr++;
261
            }
262
            gif_put_bits_rev(&p, 9, v);
263 ba19f848 Fabrice Bellard
            if (--w == 0) {
264
                w = width;
265
                buf += linesize;
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                ptr = buf;
267
            }
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        }
269
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        if(left<=GIF_CHUNKS) {
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            gif_put_bits_rev(&p, 9, 0x101); /* end of stream */
272
            gif_flush_put_bits_rev(&p);
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        }
274
        if(pbBufPtr(&p) - p.buf > 0) {
275
            put_byte(pb, pbBufPtr(&p) - p.buf); /* byte count of the packet */
276
            put_buffer(pb, p.buf, pbBufPtr(&p) - p.buf); /* the actual buffer */
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            p.buf_ptr = p.buf; /* dequeue the bytes off the bitstream */
278
        }
279
        if(left<=GIF_CHUNKS) {
280
            put_byte(pb, 0x00); /* end of image block */
281
        }
282
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        left-=GIF_CHUNKS;
284
    }
285 ba19f848 Fabrice Bellard
    return 0;
286
}
287
288
typedef struct {
289 0c1a9eda Zdenek Kabelac
    int64_t time, file_time;
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    uint8_t buffer[100]; /* data chunks */
291 ba19f848 Fabrice Bellard
} GIFContext;
292
293
static int gif_write_header(AVFormatContext *s)
294
{
295
    GIFContext *gif = s->priv_data;
296
    ByteIOContext *pb = &s->pb;
297
    AVCodecContext *enc, *video_enc;
298 14bea432 Michael Niedermayer
    int i, width, height/*, rate*/;
299 ba19f848 Fabrice Bellard
300
/* XXX: do we reject audio streams or just ignore them ?
301
    if(s->nb_streams > 1)
302
        return -1;
303
*/
304
    gif->time = 0;
305
    gif->file_time = 0;
306
307
    video_enc = NULL;
308
    for(i=0;i<s->nb_streams;i++) {
309
        enc = &s->streams[i]->codec;
310
        if (enc->codec_type != CODEC_TYPE_AUDIO)
311
            video_enc = enc;
312
    }
313
314
    if (!video_enc) {
315
        av_free(gif);
316
        return -1;
317
    } else {
318
        width = video_enc->width;
319
        height = video_enc->height;
320 14bea432 Michael Niedermayer
//        rate = video_enc->frame_rate;
321 ba19f848 Fabrice Bellard
    }
322
323
    /* XXX: is it allowed ? seems to work so far... */
324
    video_enc->pix_fmt = PIX_FMT_RGB24;
325
326 84ab361f Fabrice Bellard
    gif_image_write_header(pb, width, height, NULL);
327 ba19f848 Fabrice Bellard
328
    put_flush_packet(&s->pb);
329
    return 0;
330
}
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static int gif_write_video(AVFormatContext *s, 
333 49057904 Fabrice Bellard
                           AVCodecContext *enc, const uint8_t *buf, int size)
334 ba19f848 Fabrice Bellard
{
335
    ByteIOContext *pb = &s->pb;
336
    GIFContext *gif = s->priv_data;
337
    int jiffies;
338 0c1a9eda Zdenek Kabelac
    int64_t delay;
339 ba19f848 Fabrice Bellard
340
    /* graphic control extension block */
341
    put_byte(pb, 0x21);
342
    put_byte(pb, 0xf9);
343
    put_byte(pb, 0x04); /* block size */
344
    put_byte(pb, 0x04); /* flags */
345
    
346
    /* 1 jiffy is 1/70 s */
347
    /* the delay_time field indicates the number of jiffies - 1 */
348
    delay = gif->file_time - gif->time;
349
350
    /* XXX: should use delay, in order to be more accurate */
351
    /* instead of using the same rounded value each time */
352
    /* XXX: don't even remember if I really use it for now */
353 14bea432 Michael Niedermayer
    jiffies = (70*enc->frame_rate_base/enc->frame_rate) - 1;
354 ba19f848 Fabrice Bellard
355
    put_le16(pb, jiffies);
356
357
    put_byte(pb, 0x1f); /* transparent color index */
358
    put_byte(pb, 0x00);
359
360
    gif_image_write_image(pb, 0, 0, enc->width, enc->height,
361 84ab361f Fabrice Bellard
                          buf, enc->width * 3, PIX_FMT_RGB24);
362 6cea494e Zdenek Kabelac
363
    put_flush_packet(&s->pb);
364
    return 0;
365
}
366
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static int gif_write_packet(AVFormatContext *s, int stream_index, 
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                            const uint8_t *buf, int size, int64_t pts)
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{
370
    AVCodecContext *codec = &s->streams[stream_index]->codec;
371
    if (codec->codec_type == CODEC_TYPE_AUDIO)
372
        return 0; /* just ignore audio */
373
    else
374
        return gif_write_video(s, codec, buf, size);
375
}
376
377
static int gif_write_trailer(AVFormatContext *s)
378
{
379
    ByteIOContext *pb = &s->pb;
380
381
    put_byte(pb, 0x3b);
382
    put_flush_packet(&s->pb);
383
    return 0;
384
}
385
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/* better than nothing gif image writer */
387
int gif_write(ByteIOContext *pb, AVImageInfo *info)
388
{
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    gif_image_write_header(pb, info->width, info->height, 
390
                           (uint32_t *)info->pict.data[1]);
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    gif_image_write_image(pb, 0, 0, info->width, info->height, 
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                          info->pict.data[0], info->pict.linesize[0], 
393
                          PIX_FMT_PAL8);
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    put_byte(pb, 0x3b);
395
    put_flush_packet(pb);
396
    return 0;
397
}
398
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static AVOutputFormat gif_oformat = {
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    "gif",
401
    "GIF Animation",
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    "image/gif",
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    "gif",
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    sizeof(GIFContext),
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    CODEC_ID_NONE,
406
    CODEC_ID_RAWVIDEO,
407
    gif_write_header,
408
    gif_write_packet,
409
    gif_write_trailer,
410
};
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extern AVInputFormat gif_iformat;
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414
int gif_init(void)
415
{
416
    av_register_output_format(&gif_oformat);
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    av_register_input_format(&gif_iformat);
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    return 0;
419
}