changing AVCodecContext codec -> *codec in AVStream so additions to AVCodecContext...
[libav.git] / libavformat / gif.c
1 /*
2 * Animated GIF encoder
3 * Copyright (c) 2000 Fabrice Bellard.
4 *
5 * 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 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
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).
28 *
29 * Reference documents:
30 * http://www.goice.co.jp/member/mo/formats/gif.html
31 * http://astronomy.swin.edu.au/pbourke/dataformats/gif/
32 * http://www.dcs.ed.ac.uk/home/mxr/gfx/2d/GIF89a.txt
33 *
34 * this url claims to have an LZW algorithm not covered by Unisys patent:
35 * 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 #include "bitstream.h"
42
43 /* bitstream minipacket size */
44 #define GIF_CHUNKS 100
45
46 /* slows down the decoding (and some browsers don't like it) */
47 /* update on the 'some browsers don't like it issue from above: this was probably due to missing 'Data Sub-block Terminator' (byte 19) in the app_header */
48 #define GIF_ADD_APP_HEADER // required to enable looping of animated gif
49
50 typedef struct {
51 unsigned char r;
52 unsigned char g;
53 unsigned char b;
54 } rgb_triplet;
55
56 /* we use the standard 216 color palette */
57
58 /* this script was used to create the palette:
59 * 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
60 * echo -n "{ 0x$r, 0x$g, 0x$b }, "; done; echo ""; done; done
61 */
62
63 static const rgb_triplet gif_clut[216] = {
64 { 0x00, 0x00, 0x00 }, { 0x00, 0x00, 0x33 }, { 0x00, 0x00, 0x66 }, { 0x00, 0x00, 0x99 }, { 0x00, 0x00, 0xcc }, { 0x00, 0x00, 0xff },
65 { 0x00, 0x33, 0x00 }, { 0x00, 0x33, 0x33 }, { 0x00, 0x33, 0x66 }, { 0x00, 0x33, 0x99 }, { 0x00, 0x33, 0xcc }, { 0x00, 0x33, 0xff },
66 { 0x00, 0x66, 0x00 }, { 0x00, 0x66, 0x33 }, { 0x00, 0x66, 0x66 }, { 0x00, 0x66, 0x99 }, { 0x00, 0x66, 0xcc }, { 0x00, 0x66, 0xff },
67 { 0x00, 0x99, 0x00 }, { 0x00, 0x99, 0x33 }, { 0x00, 0x99, 0x66 }, { 0x00, 0x99, 0x99 }, { 0x00, 0x99, 0xcc }, { 0x00, 0x99, 0xff },
68 { 0x00, 0xcc, 0x00 }, { 0x00, 0xcc, 0x33 }, { 0x00, 0xcc, 0x66 }, { 0x00, 0xcc, 0x99 }, { 0x00, 0xcc, 0xcc }, { 0x00, 0xcc, 0xff },
69 { 0x00, 0xff, 0x00 }, { 0x00, 0xff, 0x33 }, { 0x00, 0xff, 0x66 }, { 0x00, 0xff, 0x99 }, { 0x00, 0xff, 0xcc }, { 0x00, 0xff, 0xff },
70 { 0x33, 0x00, 0x00 }, { 0x33, 0x00, 0x33 }, { 0x33, 0x00, 0x66 }, { 0x33, 0x00, 0x99 }, { 0x33, 0x00, 0xcc }, { 0x33, 0x00, 0xff },
71 { 0x33, 0x33, 0x00 }, { 0x33, 0x33, 0x33 }, { 0x33, 0x33, 0x66 }, { 0x33, 0x33, 0x99 }, { 0x33, 0x33, 0xcc }, { 0x33, 0x33, 0xff },
72 { 0x33, 0x66, 0x00 }, { 0x33, 0x66, 0x33 }, { 0x33, 0x66, 0x66 }, { 0x33, 0x66, 0x99 }, { 0x33, 0x66, 0xcc }, { 0x33, 0x66, 0xff },
73 { 0x33, 0x99, 0x00 }, { 0x33, 0x99, 0x33 }, { 0x33, 0x99, 0x66 }, { 0x33, 0x99, 0x99 }, { 0x33, 0x99, 0xcc }, { 0x33, 0x99, 0xff },
74 { 0x33, 0xcc, 0x00 }, { 0x33, 0xcc, 0x33 }, { 0x33, 0xcc, 0x66 }, { 0x33, 0xcc, 0x99 }, { 0x33, 0xcc, 0xcc }, { 0x33, 0xcc, 0xff },
75 { 0x33, 0xff, 0x00 }, { 0x33, 0xff, 0x33 }, { 0x33, 0xff, 0x66 }, { 0x33, 0xff, 0x99 }, { 0x33, 0xff, 0xcc }, { 0x33, 0xff, 0xff },
76 { 0x66, 0x00, 0x00 }, { 0x66, 0x00, 0x33 }, { 0x66, 0x00, 0x66 }, { 0x66, 0x00, 0x99 }, { 0x66, 0x00, 0xcc }, { 0x66, 0x00, 0xff },
77 { 0x66, 0x33, 0x00 }, { 0x66, 0x33, 0x33 }, { 0x66, 0x33, 0x66 }, { 0x66, 0x33, 0x99 }, { 0x66, 0x33, 0xcc }, { 0x66, 0x33, 0xff },
78 { 0x66, 0x66, 0x00 }, { 0x66, 0x66, 0x33 }, { 0x66, 0x66, 0x66 }, { 0x66, 0x66, 0x99 }, { 0x66, 0x66, 0xcc }, { 0x66, 0x66, 0xff },
79 { 0x66, 0x99, 0x00 }, { 0x66, 0x99, 0x33 }, { 0x66, 0x99, 0x66 }, { 0x66, 0x99, 0x99 }, { 0x66, 0x99, 0xcc }, { 0x66, 0x99, 0xff },
80 { 0x66, 0xcc, 0x00 }, { 0x66, 0xcc, 0x33 }, { 0x66, 0xcc, 0x66 }, { 0x66, 0xcc, 0x99 }, { 0x66, 0xcc, 0xcc }, { 0x66, 0xcc, 0xff },
81 { 0x66, 0xff, 0x00 }, { 0x66, 0xff, 0x33 }, { 0x66, 0xff, 0x66 }, { 0x66, 0xff, 0x99 }, { 0x66, 0xff, 0xcc }, { 0x66, 0xff, 0xff },
82 { 0x99, 0x00, 0x00 }, { 0x99, 0x00, 0x33 }, { 0x99, 0x00, 0x66 }, { 0x99, 0x00, 0x99 }, { 0x99, 0x00, 0xcc }, { 0x99, 0x00, 0xff },
83 { 0x99, 0x33, 0x00 }, { 0x99, 0x33, 0x33 }, { 0x99, 0x33, 0x66 }, { 0x99, 0x33, 0x99 }, { 0x99, 0x33, 0xcc }, { 0x99, 0x33, 0xff },
84 { 0x99, 0x66, 0x00 }, { 0x99, 0x66, 0x33 }, { 0x99, 0x66, 0x66 }, { 0x99, 0x66, 0x99 }, { 0x99, 0x66, 0xcc }, { 0x99, 0x66, 0xff },
85 { 0x99, 0x99, 0x00 }, { 0x99, 0x99, 0x33 }, { 0x99, 0x99, 0x66 }, { 0x99, 0x99, 0x99 }, { 0x99, 0x99, 0xcc }, { 0x99, 0x99, 0xff },
86 { 0x99, 0xcc, 0x00 }, { 0x99, 0xcc, 0x33 }, { 0x99, 0xcc, 0x66 }, { 0x99, 0xcc, 0x99 }, { 0x99, 0xcc, 0xcc }, { 0x99, 0xcc, 0xff },
87 { 0x99, 0xff, 0x00 }, { 0x99, 0xff, 0x33 }, { 0x99, 0xff, 0x66 }, { 0x99, 0xff, 0x99 }, { 0x99, 0xff, 0xcc }, { 0x99, 0xff, 0xff },
88 { 0xcc, 0x00, 0x00 }, { 0xcc, 0x00, 0x33 }, { 0xcc, 0x00, 0x66 }, { 0xcc, 0x00, 0x99 }, { 0xcc, 0x00, 0xcc }, { 0xcc, 0x00, 0xff },
89 { 0xcc, 0x33, 0x00 }, { 0xcc, 0x33, 0x33 }, { 0xcc, 0x33, 0x66 }, { 0xcc, 0x33, 0x99 }, { 0xcc, 0x33, 0xcc }, { 0xcc, 0x33, 0xff },
90 { 0xcc, 0x66, 0x00 }, { 0xcc, 0x66, 0x33 }, { 0xcc, 0x66, 0x66 }, { 0xcc, 0x66, 0x99 }, { 0xcc, 0x66, 0xcc }, { 0xcc, 0x66, 0xff },
91 { 0xcc, 0x99, 0x00 }, { 0xcc, 0x99, 0x33 }, { 0xcc, 0x99, 0x66 }, { 0xcc, 0x99, 0x99 }, { 0xcc, 0x99, 0xcc }, { 0xcc, 0x99, 0xff },
92 { 0xcc, 0xcc, 0x00 }, { 0xcc, 0xcc, 0x33 }, { 0xcc, 0xcc, 0x66 }, { 0xcc, 0xcc, 0x99 }, { 0xcc, 0xcc, 0xcc }, { 0xcc, 0xcc, 0xff },
93 { 0xcc, 0xff, 0x00 }, { 0xcc, 0xff, 0x33 }, { 0xcc, 0xff, 0x66 }, { 0xcc, 0xff, 0x99 }, { 0xcc, 0xff, 0xcc }, { 0xcc, 0xff, 0xff },
94 { 0xff, 0x00, 0x00 }, { 0xff, 0x00, 0x33 }, { 0xff, 0x00, 0x66 }, { 0xff, 0x00, 0x99 }, { 0xff, 0x00, 0xcc }, { 0xff, 0x00, 0xff },
95 { 0xff, 0x33, 0x00 }, { 0xff, 0x33, 0x33 }, { 0xff, 0x33, 0x66 }, { 0xff, 0x33, 0x99 }, { 0xff, 0x33, 0xcc }, { 0xff, 0x33, 0xff },
96 { 0xff, 0x66, 0x00 }, { 0xff, 0x66, 0x33 }, { 0xff, 0x66, 0x66 }, { 0xff, 0x66, 0x99 }, { 0xff, 0x66, 0xcc }, { 0xff, 0x66, 0xff },
97 { 0xff, 0x99, 0x00 }, { 0xff, 0x99, 0x33 }, { 0xff, 0x99, 0x66 }, { 0xff, 0x99, 0x99 }, { 0xff, 0x99, 0xcc }, { 0xff, 0x99, 0xff },
98 { 0xff, 0xcc, 0x00 }, { 0xff, 0xcc, 0x33 }, { 0xff, 0xcc, 0x66 }, { 0xff, 0xcc, 0x99 }, { 0xff, 0xcc, 0xcc }, { 0xff, 0xcc, 0xff },
99 { 0xff, 0xff, 0x00 }, { 0xff, 0xff, 0x33 }, { 0xff, 0xff, 0x66 }, { 0xff, 0xff, 0x99 }, { 0xff, 0xff, 0xcc }, { 0xff, 0xff, 0xff },
100 };
101
102 /* The GIF format uses reversed order for bitstreams... */
103 /* at least they don't use PDP_ENDIAN :) */
104 /* so we 'extend' PutBitContext. hmmm, OOP :) */
105 /* seems this thing changed slightly since I wrote it... */
106
107 #ifdef ALT_BITSTREAM_WRITER
108 # error no ALT_BITSTREAM_WRITER support for now
109 #endif
110
111 static void gif_put_bits_rev(PutBitContext *s, int n, unsigned int value)
112 {
113 unsigned int bit_buf;
114 int bit_cnt;
115
116 #ifdef STATS
117 st_out_bit_counts[st_current_index] += n;
118 #endif
119 // printf("put_bits=%d %x\n", n, value);
120 assert(n == 32 || value < (1U << n));
121
122 bit_buf = s->bit_buf;
123 bit_cnt = 32 - s->bit_left; /* XXX:lazyness... was = s->bit_cnt; */
124
125 // printf("n=%d value=%x cnt=%d buf=%x\n", n, value, bit_cnt, bit_buf);
126 /* XXX: optimize */
127 if (n < (32-bit_cnt)) {
128 bit_buf |= value << (bit_cnt);
129 bit_cnt+=n;
130 } else {
131 bit_buf |= value << (bit_cnt);
132
133 *s->buf_ptr = bit_buf & 0xff;
134 s->buf_ptr[1] = (bit_buf >> 8) & 0xff;
135 s->buf_ptr[2] = (bit_buf >> 16) & 0xff;
136 s->buf_ptr[3] = (bit_buf >> 24) & 0xff;
137
138 //printf("bitbuf = %08x\n", bit_buf);
139 s->buf_ptr+=4;
140 if (s->buf_ptr >= s->buf_end)
141 puts("bit buffer overflow !!"); // should never happen ! who got rid of the callback ???
142 // flush_buffer_rev(s);
143 bit_cnt=bit_cnt + n - 32;
144 if (bit_cnt == 0) {
145 bit_buf = 0;
146 } else {
147 bit_buf = value >> (n - bit_cnt);
148 }
149 }
150
151 s->bit_buf = bit_buf;
152 s->bit_left = 32 - bit_cnt;
153 }
154
155 /* pad the end of the output stream with zeros */
156 static void gif_flush_put_bits_rev(PutBitContext *s)
157 {
158 while (s->bit_left < 32) {
159 /* XXX: should test end of buffer */
160 *s->buf_ptr++=s->bit_buf & 0xff;
161 s->bit_buf>>=8;
162 s->bit_left+=8;
163 }
164 // flush_buffer_rev(s);
165 s->bit_left=32;
166 s->bit_buf=0;
167 }
168
169 /* !RevPutBitContext */
170
171 /* GIF header */
172 static int gif_image_write_header(ByteIOContext *pb,
173 int width, int height, int loop_count,
174 uint32_t *palette)
175 {
176 int i;
177 unsigned int v;
178
179 put_tag(pb, "GIF");
180 put_tag(pb, "89a");
181 put_le16(pb, width);
182 put_le16(pb, height);
183
184 put_byte(pb, 0xf7); /* flags: global clut, 256 entries */
185 put_byte(pb, 0x1f); /* background color index */
186 put_byte(pb, 0); /* aspect ratio */
187
188 /* the global palette */
189 if (!palette) {
190 put_buffer(pb, (unsigned char *)gif_clut, 216*3);
191 for(i=0;i<((256-216)*3);i++)
192 put_byte(pb, 0);
193 } else {
194 for(i=0;i<256;i++) {
195 v = palette[i];
196 put_byte(pb, (v >> 16) & 0xff);
197 put_byte(pb, (v >> 8) & 0xff);
198 put_byte(pb, (v) & 0xff);
199 }
200 }
201
202 /* update: this is the 'NETSCAPE EXTENSION' that allows for looped animated gif
203 see http://members.aol.com/royalef/gifabout.htm#net-extension
204
205 byte 1 : 33 (hex 0x21) GIF Extension code
206 byte 2 : 255 (hex 0xFF) Application Extension Label
207 byte 3 : 11 (hex (0x0B) Length of Application Block
208 (eleven bytes of data to follow)
209 bytes 4 to 11 : "NETSCAPE"
210 bytes 12 to 14 : "2.0"
211 byte 15 : 3 (hex 0x03) Length of Data Sub-Block
212 (three bytes of data to follow)
213 byte 16 : 1 (hex 0x01)
214 bytes 17 to 18 : 0 to 65535, an unsigned integer in
215 lo-hi byte format. This indicate the
216 number of iterations the loop should
217 be executed.
218 bytes 19 : 0 (hex 0x00) a Data Sub-block Terminator
219 */
220
221 /* application extension header */
222 #ifdef GIF_ADD_APP_HEADER
223 if (loop_count >= 0 && loop_count <= 65535) {
224 put_byte(pb, 0x21);
225 put_byte(pb, 0xff);
226 put_byte(pb, 0x0b);
227 put_tag(pb, "NETSCAPE2.0"); // bytes 4 to 14
228 put_byte(pb, 0x03); // byte 15
229 put_byte(pb, 0x01); // byte 16
230 put_le16(pb, (uint16_t)loop_count);
231 put_byte(pb, 0x00); // byte 19
232 }
233 #endif
234 return 0;
235 }
236
237 /* this is maybe slow, but allows for extensions */
238 static inline unsigned char gif_clut_index(uint8_t r, uint8_t g, uint8_t b)
239 {
240 return ((((r)/47)%6)*6*6+(((g)/47)%6)*6+(((b)/47)%6));
241 }
242
243
244 static int gif_image_write_image(ByteIOContext *pb,
245 int x1, int y1, int width, int height,
246 const uint8_t *buf, int linesize, int pix_fmt)
247 {
248 PutBitContext p;
249 uint8_t buffer[200]; /* 100 * 9 / 8 = 113 */
250 int i, left, w, v;
251 const uint8_t *ptr;
252 /* image block */
253
254 put_byte(pb, 0x2c);
255 put_le16(pb, x1);
256 put_le16(pb, y1);
257 put_le16(pb, width);
258 put_le16(pb, height);
259 put_byte(pb, 0x00); /* flags */
260 /* no local clut */
261
262 put_byte(pb, 0x08);
263
264 left= width * height;
265
266 init_put_bits(&p, buffer, 130);
267
268 /*
269 * the thing here is the bitstream is written as little packets, with a size byte before
270 * but it's still the same bitstream between packets (no flush !)
271 */
272 ptr = buf;
273 w = width;
274 while(left>0) {
275
276 gif_put_bits_rev(&p, 9, 0x0100); /* clear code */
277
278 for(i=(left<GIF_CHUNKS)?left:GIF_CHUNKS;i;i--) {
279 if (pix_fmt == PIX_FMT_RGB24) {
280 v = gif_clut_index(ptr[0], ptr[1], ptr[2]);
281 ptr+=3;
282 } else {
283 v = *ptr++;
284 }
285 gif_put_bits_rev(&p, 9, v);
286 if (--w == 0) {
287 w = width;
288 buf += linesize;
289 ptr = buf;
290 }
291 }
292
293 if(left<=GIF_CHUNKS) {
294 gif_put_bits_rev(&p, 9, 0x101); /* end of stream */
295 gif_flush_put_bits_rev(&p);
296 }
297 if(pbBufPtr(&p) - p.buf > 0) {
298 put_byte(pb, pbBufPtr(&p) - p.buf); /* byte count of the packet */
299 put_buffer(pb, p.buf, pbBufPtr(&p) - p.buf); /* the actual buffer */
300 p.buf_ptr = p.buf; /* dequeue the bytes off the bitstream */
301 }
302 left-=GIF_CHUNKS;
303 }
304 put_byte(pb, 0x00); /* end of image block */
305
306 return 0;
307 }
308
309 typedef struct {
310 int64_t time, file_time;
311 uint8_t buffer[100]; /* data chunks */
312 } GIFContext;
313
314 static int gif_write_header(AVFormatContext *s)
315 {
316 GIFContext *gif = s->priv_data;
317 ByteIOContext *pb = &s->pb;
318 AVCodecContext *enc, *video_enc;
319 int i, width, height, loop_count /*, rate*/;
320
321 /* XXX: do we reject audio streams or just ignore them ?
322 if(s->nb_streams > 1)
323 return -1;
324 */
325 gif->time = 0;
326 gif->file_time = 0;
327
328 video_enc = NULL;
329 for(i=0;i<s->nb_streams;i++) {
330 enc = s->streams[i]->codec;
331 if (enc->codec_type != CODEC_TYPE_AUDIO)
332 video_enc = enc;
333 }
334
335 if (!video_enc) {
336 av_free(gif);
337 return -1;
338 } else {
339 width = video_enc->width;
340 height = video_enc->height;
341 loop_count = s->loop_output;
342 // rate = video_enc->time_base.den;
343 }
344
345 /* XXX: is it allowed ? seems to work so far... */
346 video_enc->pix_fmt = PIX_FMT_RGB24;
347
348 gif_image_write_header(pb, width, height, loop_count, NULL);
349
350 put_flush_packet(&s->pb);
351 return 0;
352 }
353
354 static int gif_write_video(AVFormatContext *s,
355 AVCodecContext *enc, const uint8_t *buf, int size)
356 {
357 ByteIOContext *pb = &s->pb;
358 GIFContext *gif = s->priv_data;
359 int jiffies;
360 int64_t delay;
361
362 /* graphic control extension block */
363 put_byte(pb, 0x21);
364 put_byte(pb, 0xf9);
365 put_byte(pb, 0x04); /* block size */
366 put_byte(pb, 0x04); /* flags */
367
368 /* 1 jiffy is 1/70 s */
369 /* the delay_time field indicates the number of jiffies - 1 */
370 delay = gif->file_time - gif->time;
371
372 /* XXX: should use delay, in order to be more accurate */
373 /* instead of using the same rounded value each time */
374 /* XXX: don't even remember if I really use it for now */
375 jiffies = (70*enc->time_base.num/enc->time_base.den) - 1;
376
377 put_le16(pb, jiffies);
378
379 put_byte(pb, 0x1f); /* transparent color index */
380 put_byte(pb, 0x00);
381
382 gif_image_write_image(pb, 0, 0, enc->width, enc->height,
383 buf, enc->width * 3, PIX_FMT_RGB24);
384
385 put_flush_packet(&s->pb);
386 return 0;
387 }
388
389 static int gif_write_packet(AVFormatContext *s, AVPacket *pkt)
390 {
391 AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
392 if (codec->codec_type == CODEC_TYPE_AUDIO)
393 return 0; /* just ignore audio */
394 else
395 return gif_write_video(s, codec, pkt->data, pkt->size);
396 }
397
398 static int gif_write_trailer(AVFormatContext *s)
399 {
400 ByteIOContext *pb = &s->pb;
401
402 put_byte(pb, 0x3b);
403 put_flush_packet(&s->pb);
404 return 0;
405 }
406
407 /* better than nothing gif image writer */
408 int gif_write(ByteIOContext *pb, AVImageInfo *info)
409 {
410 gif_image_write_header(pb, info->width, info->height, AVFMT_NOOUTPUTLOOP,
411 (uint32_t *)info->pict.data[1]);
412 gif_image_write_image(pb, 0, 0, info->width, info->height,
413 info->pict.data[0], info->pict.linesize[0],
414 PIX_FMT_PAL8);
415 put_byte(pb, 0x3b);
416 put_flush_packet(pb);
417 return 0;
418 }
419
420 static AVOutputFormat gif_oformat = {
421 "gif",
422 "GIF Animation",
423 "image/gif",
424 "gif",
425 sizeof(GIFContext),
426 CODEC_ID_NONE,
427 CODEC_ID_RAWVIDEO,
428 gif_write_header,
429 gif_write_packet,
430 gif_write_trailer,
431 };
432
433 extern AVInputFormat gif_iformat;
434
435 int gif_init(void)
436 {
437 av_register_output_format(&gif_oformat);
438 av_register_input_format(&gif_iformat);
439 return 0;
440 }