You've already forked FFmpeg
							
							
				mirror of
				https://github.com/FFmpeg/FFmpeg.git
				synced 2025-10-30 23:18:11 +02:00 
			
		
		
		
	change gif muxer to simple gif encoder
Originally committed as revision 6874 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
		| @@ -82,6 +82,7 @@ OBJS-$(CONFIG_FLIC_DECODER)            += flicvideo.o | ||||
| OBJS-$(CONFIG_FOURXM_DECODER)          += 4xm.o | ||||
| OBJS-$(CONFIG_FRAPS_DECODER)           += fraps.o | ||||
| OBJS-$(CONFIG_GIF_DECODER)             += gifdec.o lzw.o | ||||
| OBJS-$(CONFIG_GIF_ENCODER)             += gif.o | ||||
| OBJS-$(CONFIG_H261_DECODER)            += h261.o | ||||
| OBJS-$(CONFIG_H261_ENCODER)            += h261.o | ||||
| OBJS-$(CONFIG_H264_DECODER)            += h264.o | ||||
|   | ||||
| @@ -68,6 +68,9 @@ void avcodec_register_all(void) | ||||
| #ifdef CONFIG_FLAC_ENCODER | ||||
|     register_avcodec(&flac_encoder); | ||||
| #endif | ||||
| #ifdef CONFIG_GIF_ENCODER | ||||
|     register_avcodec(&gif_encoder); | ||||
| #endif | ||||
| #ifdef CONFIG_XVID | ||||
| #ifdef CONFIG_XVID_ENCODER | ||||
|     register_avcodec(&xvid_encoder); | ||||
|   | ||||
| @@ -37,8 +37,8 @@ extern "C" { | ||||
| #define AV_STRINGIFY(s)         AV_TOSTRING(s) | ||||
| #define AV_TOSTRING(s) #s | ||||
|  | ||||
| #define LIBAVCODEC_VERSION_INT  ((51<<16)+(23<<8)+0) | ||||
| #define LIBAVCODEC_VERSION      51.23.0 | ||||
| #define LIBAVCODEC_VERSION_INT  ((51<<16)+(24<<8)+0) | ||||
| #define LIBAVCODEC_VERSION      51.24.0 | ||||
| #define LIBAVCODEC_BUILD        LIBAVCODEC_VERSION_INT | ||||
|  | ||||
| #define LIBAVCODEC_IDENT        "Lavc" AV_STRINGIFY(LIBAVCODEC_VERSION) | ||||
| @@ -2138,6 +2138,7 @@ extern AVCodec mp3lame_encoder; | ||||
| extern AVCodec oggvorbis_encoder; | ||||
| extern AVCodec faac_encoder; | ||||
| extern AVCodec flac_encoder; | ||||
| extern AVCodec gif_encoder; | ||||
| extern AVCodec xvid_encoder; | ||||
| extern AVCodec mpeg1video_encoder; | ||||
| extern AVCodec mpeg2video_encoder; | ||||
|   | ||||
| @@ -47,4 +47,29 @@ static always_inline unsigned int bytestream_get_buffer(uint8_t **b, uint8_t *ds | ||||
|     return size; | ||||
| } | ||||
|  | ||||
| static always_inline void bytestream_put_le32(uint8_t **b, const unsigned int value) | ||||
| { | ||||
|     *(*b)++ = value; | ||||
|     *(*b)++ = value >> 8; | ||||
|     *(*b)++ = value >> 16; | ||||
|     *(*b)++ = value >> 24; | ||||
| } | ||||
|  | ||||
| static always_inline void bytestream_put_le16(uint8_t **b, const unsigned int value) | ||||
| { | ||||
|     *(*b)++ = value; | ||||
|     *(*b)++ = value >> 8; | ||||
| } | ||||
|  | ||||
| static always_inline void bytestream_put_byte(uint8_t **b, const unsigned int value) | ||||
| { | ||||
|     *(*b)++ = value; | ||||
| } | ||||
|  | ||||
| static always_inline void bytestream_put_buffer(uint8_t **b, const uint8_t *src, unsigned int size) | ||||
| { | ||||
|     memcpy(*b, src, size); | ||||
|     (*b) += size; | ||||
| } | ||||
|  | ||||
| #endif /* FFMPEG_BYTESTREAM_H */ | ||||
|   | ||||
							
								
								
									
										350
									
								
								libavcodec/gif.c
									
									
									
									
									
										Normal file
									
								
							
							
						
						
									
										350
									
								
								libavcodec/gif.c
									
									
									
									
									
										Normal file
									
								
							| @@ -0,0 +1,350 @@ | ||||
| /* | ||||
|  * GIF encoder. | ||||
|  * Copyright (c) 2000 Fabrice Bellard. | ||||
|  * Copyright (c) 2002 Francois Revol. | ||||
|  * Copyright (c) 2006 Baptiste Coudurier. | ||||
|  * | ||||
|  * 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 | ||||
|  */ | ||||
|  | ||||
| /* | ||||
|  * First version by Francois Revol revol@free.fr | ||||
|  * | ||||
|  * Features and limitations: | ||||
|  * - currently no compression is performed, | ||||
|  *   in fact the size of the data is 9/8 the size of the image in 8bpp | ||||
|  * - uses only a global standard palette | ||||
|  * - tested with IE 5.0, Opera for BeOS, NetPositive (BeOS), and Mozilla (BeOS). | ||||
|  * | ||||
|  * Reference documents: | ||||
|  * http://www.goice.co.jp/member/mo/formats/gif.html | ||||
|  * http://astronomy.swin.edu.au/pbourke/dataformats/gif/ | ||||
|  * http://www.dcs.ed.ac.uk/home/mxr/gfx/2d/GIF89a.txt | ||||
|  * | ||||
|  * this url claims to have an LZW algorithm not covered by Unisys patent: | ||||
|  * http://www.msg.net/utility/whirlgif/gifencod.html | ||||
|  * could help reduce the size of the files _a lot_... | ||||
|  * some sites mentions an RLE type compression also. | ||||
|  */ | ||||
|  | ||||
| #include "avcodec.h" | ||||
| #include "bytestream.h" | ||||
| #include "bitstream.h" | ||||
|  | ||||
| /* bitstream minipacket size */ | ||||
| #define GIF_CHUNKS 100 | ||||
|  | ||||
| /* slows down the decoding (and some browsers don't like it) */ | ||||
| /* 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 */ | ||||
| #define GIF_ADD_APP_HEADER // required to enable looping of animated gif | ||||
|  | ||||
| typedef struct { | ||||
|     unsigned char r; | ||||
|     unsigned char g; | ||||
|     unsigned char b; | ||||
| } rgb_triplet; | ||||
|  | ||||
| /* we use the standard 216 color palette */ | ||||
|  | ||||
| /* this script was used to create the palette: | ||||
|  * 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 | ||||
|  *   echo -n "{ 0x$r, 0x$g, 0x$b }, "; done; echo ""; done; done | ||||
|  */ | ||||
|  | ||||
| static const rgb_triplet gif_clut[216] = { | ||||
|     { 0x00, 0x00, 0x00 }, { 0x00, 0x00, 0x33 }, { 0x00, 0x00, 0x66 }, { 0x00, 0x00, 0x99 }, { 0x00, 0x00, 0xcc }, { 0x00, 0x00, 0xff }, | ||||
|     { 0x00, 0x33, 0x00 }, { 0x00, 0x33, 0x33 }, { 0x00, 0x33, 0x66 }, { 0x00, 0x33, 0x99 }, { 0x00, 0x33, 0xcc }, { 0x00, 0x33, 0xff }, | ||||
|     { 0x00, 0x66, 0x00 }, { 0x00, 0x66, 0x33 }, { 0x00, 0x66, 0x66 }, { 0x00, 0x66, 0x99 }, { 0x00, 0x66, 0xcc }, { 0x00, 0x66, 0xff }, | ||||
|     { 0x00, 0x99, 0x00 }, { 0x00, 0x99, 0x33 }, { 0x00, 0x99, 0x66 }, { 0x00, 0x99, 0x99 }, { 0x00, 0x99, 0xcc }, { 0x00, 0x99, 0xff }, | ||||
|     { 0x00, 0xcc, 0x00 }, { 0x00, 0xcc, 0x33 }, { 0x00, 0xcc, 0x66 }, { 0x00, 0xcc, 0x99 }, { 0x00, 0xcc, 0xcc }, { 0x00, 0xcc, 0xff }, | ||||
|     { 0x00, 0xff, 0x00 }, { 0x00, 0xff, 0x33 }, { 0x00, 0xff, 0x66 }, { 0x00, 0xff, 0x99 }, { 0x00, 0xff, 0xcc }, { 0x00, 0xff, 0xff }, | ||||
|     { 0x33, 0x00, 0x00 }, { 0x33, 0x00, 0x33 }, { 0x33, 0x00, 0x66 }, { 0x33, 0x00, 0x99 }, { 0x33, 0x00, 0xcc }, { 0x33, 0x00, 0xff }, | ||||
|     { 0x33, 0x33, 0x00 }, { 0x33, 0x33, 0x33 }, { 0x33, 0x33, 0x66 }, { 0x33, 0x33, 0x99 }, { 0x33, 0x33, 0xcc }, { 0x33, 0x33, 0xff }, | ||||
|     { 0x33, 0x66, 0x00 }, { 0x33, 0x66, 0x33 }, { 0x33, 0x66, 0x66 }, { 0x33, 0x66, 0x99 }, { 0x33, 0x66, 0xcc }, { 0x33, 0x66, 0xff }, | ||||
|     { 0x33, 0x99, 0x00 }, { 0x33, 0x99, 0x33 }, { 0x33, 0x99, 0x66 }, { 0x33, 0x99, 0x99 }, { 0x33, 0x99, 0xcc }, { 0x33, 0x99, 0xff }, | ||||
|     { 0x33, 0xcc, 0x00 }, { 0x33, 0xcc, 0x33 }, { 0x33, 0xcc, 0x66 }, { 0x33, 0xcc, 0x99 }, { 0x33, 0xcc, 0xcc }, { 0x33, 0xcc, 0xff }, | ||||
|     { 0x33, 0xff, 0x00 }, { 0x33, 0xff, 0x33 }, { 0x33, 0xff, 0x66 }, { 0x33, 0xff, 0x99 }, { 0x33, 0xff, 0xcc }, { 0x33, 0xff, 0xff }, | ||||
|     { 0x66, 0x00, 0x00 }, { 0x66, 0x00, 0x33 }, { 0x66, 0x00, 0x66 }, { 0x66, 0x00, 0x99 }, { 0x66, 0x00, 0xcc }, { 0x66, 0x00, 0xff }, | ||||
|     { 0x66, 0x33, 0x00 }, { 0x66, 0x33, 0x33 }, { 0x66, 0x33, 0x66 }, { 0x66, 0x33, 0x99 }, { 0x66, 0x33, 0xcc }, { 0x66, 0x33, 0xff }, | ||||
|     { 0x66, 0x66, 0x00 }, { 0x66, 0x66, 0x33 }, { 0x66, 0x66, 0x66 }, { 0x66, 0x66, 0x99 }, { 0x66, 0x66, 0xcc }, { 0x66, 0x66, 0xff }, | ||||
|     { 0x66, 0x99, 0x00 }, { 0x66, 0x99, 0x33 }, { 0x66, 0x99, 0x66 }, { 0x66, 0x99, 0x99 }, { 0x66, 0x99, 0xcc }, { 0x66, 0x99, 0xff }, | ||||
|     { 0x66, 0xcc, 0x00 }, { 0x66, 0xcc, 0x33 }, { 0x66, 0xcc, 0x66 }, { 0x66, 0xcc, 0x99 }, { 0x66, 0xcc, 0xcc }, { 0x66, 0xcc, 0xff }, | ||||
|     { 0x66, 0xff, 0x00 }, { 0x66, 0xff, 0x33 }, { 0x66, 0xff, 0x66 }, { 0x66, 0xff, 0x99 }, { 0x66, 0xff, 0xcc }, { 0x66, 0xff, 0xff }, | ||||
|     { 0x99, 0x00, 0x00 }, { 0x99, 0x00, 0x33 }, { 0x99, 0x00, 0x66 }, { 0x99, 0x00, 0x99 }, { 0x99, 0x00, 0xcc }, { 0x99, 0x00, 0xff }, | ||||
|     { 0x99, 0x33, 0x00 }, { 0x99, 0x33, 0x33 }, { 0x99, 0x33, 0x66 }, { 0x99, 0x33, 0x99 }, { 0x99, 0x33, 0xcc }, { 0x99, 0x33, 0xff }, | ||||
|     { 0x99, 0x66, 0x00 }, { 0x99, 0x66, 0x33 }, { 0x99, 0x66, 0x66 }, { 0x99, 0x66, 0x99 }, { 0x99, 0x66, 0xcc }, { 0x99, 0x66, 0xff }, | ||||
|     { 0x99, 0x99, 0x00 }, { 0x99, 0x99, 0x33 }, { 0x99, 0x99, 0x66 }, { 0x99, 0x99, 0x99 }, { 0x99, 0x99, 0xcc }, { 0x99, 0x99, 0xff }, | ||||
|     { 0x99, 0xcc, 0x00 }, { 0x99, 0xcc, 0x33 }, { 0x99, 0xcc, 0x66 }, { 0x99, 0xcc, 0x99 }, { 0x99, 0xcc, 0xcc }, { 0x99, 0xcc, 0xff }, | ||||
|     { 0x99, 0xff, 0x00 }, { 0x99, 0xff, 0x33 }, { 0x99, 0xff, 0x66 }, { 0x99, 0xff, 0x99 }, { 0x99, 0xff, 0xcc }, { 0x99, 0xff, 0xff }, | ||||
|     { 0xcc, 0x00, 0x00 }, { 0xcc, 0x00, 0x33 }, { 0xcc, 0x00, 0x66 }, { 0xcc, 0x00, 0x99 }, { 0xcc, 0x00, 0xcc }, { 0xcc, 0x00, 0xff }, | ||||
|     { 0xcc, 0x33, 0x00 }, { 0xcc, 0x33, 0x33 }, { 0xcc, 0x33, 0x66 }, { 0xcc, 0x33, 0x99 }, { 0xcc, 0x33, 0xcc }, { 0xcc, 0x33, 0xff }, | ||||
|     { 0xcc, 0x66, 0x00 }, { 0xcc, 0x66, 0x33 }, { 0xcc, 0x66, 0x66 }, { 0xcc, 0x66, 0x99 }, { 0xcc, 0x66, 0xcc }, { 0xcc, 0x66, 0xff }, | ||||
|     { 0xcc, 0x99, 0x00 }, { 0xcc, 0x99, 0x33 }, { 0xcc, 0x99, 0x66 }, { 0xcc, 0x99, 0x99 }, { 0xcc, 0x99, 0xcc }, { 0xcc, 0x99, 0xff }, | ||||
|     { 0xcc, 0xcc, 0x00 }, { 0xcc, 0xcc, 0x33 }, { 0xcc, 0xcc, 0x66 }, { 0xcc, 0xcc, 0x99 }, { 0xcc, 0xcc, 0xcc }, { 0xcc, 0xcc, 0xff }, | ||||
|     { 0xcc, 0xff, 0x00 }, { 0xcc, 0xff, 0x33 }, { 0xcc, 0xff, 0x66 }, { 0xcc, 0xff, 0x99 }, { 0xcc, 0xff, 0xcc }, { 0xcc, 0xff, 0xff }, | ||||
|     { 0xff, 0x00, 0x00 }, { 0xff, 0x00, 0x33 }, { 0xff, 0x00, 0x66 }, { 0xff, 0x00, 0x99 }, { 0xff, 0x00, 0xcc }, { 0xff, 0x00, 0xff }, | ||||
|     { 0xff, 0x33, 0x00 }, { 0xff, 0x33, 0x33 }, { 0xff, 0x33, 0x66 }, { 0xff, 0x33, 0x99 }, { 0xff, 0x33, 0xcc }, { 0xff, 0x33, 0xff }, | ||||
|     { 0xff, 0x66, 0x00 }, { 0xff, 0x66, 0x33 }, { 0xff, 0x66, 0x66 }, { 0xff, 0x66, 0x99 }, { 0xff, 0x66, 0xcc }, { 0xff, 0x66, 0xff }, | ||||
|     { 0xff, 0x99, 0x00 }, { 0xff, 0x99, 0x33 }, { 0xff, 0x99, 0x66 }, { 0xff, 0x99, 0x99 }, { 0xff, 0x99, 0xcc }, { 0xff, 0x99, 0xff }, | ||||
|     { 0xff, 0xcc, 0x00 }, { 0xff, 0xcc, 0x33 }, { 0xff, 0xcc, 0x66 }, { 0xff, 0xcc, 0x99 }, { 0xff, 0xcc, 0xcc }, { 0xff, 0xcc, 0xff }, | ||||
|     { 0xff, 0xff, 0x00 }, { 0xff, 0xff, 0x33 }, { 0xff, 0xff, 0x66 }, { 0xff, 0xff, 0x99 }, { 0xff, 0xff, 0xcc }, { 0xff, 0xff, 0xff }, | ||||
| }; | ||||
|  | ||||
| /* The GIF format uses reversed order for bitstreams... */ | ||||
| /* at least they don't use PDP_ENDIAN :) */ | ||||
| /* so we 'extend' PutBitContext. hmmm, OOP :) */ | ||||
| /* seems this thing changed slightly since I wrote it... */ | ||||
|  | ||||
| #ifdef ALT_BITSTREAM_WRITER | ||||
| # error no ALT_BITSTREAM_WRITER support for now | ||||
| #endif | ||||
|  | ||||
| static void gif_put_bits_rev(PutBitContext *s, int n, unsigned int value) | ||||
| { | ||||
|     unsigned int bit_buf; | ||||
|     int bit_cnt; | ||||
|  | ||||
|     //    printf("put_bits=%d %x\n", n, value); | ||||
|     assert(n == 32 || value < (1U << n)); | ||||
|  | ||||
|     bit_buf = s->bit_buf; | ||||
|     bit_cnt = 32 - s->bit_left; /* XXX:lazyness... was = s->bit_cnt; */ | ||||
|  | ||||
|     //    printf("n=%d value=%x cnt=%d buf=%x\n", n, value, bit_cnt, bit_buf); | ||||
|     /* XXX: optimize */ | ||||
|     if (n < (32-bit_cnt)) { | ||||
|         bit_buf |= value << (bit_cnt); | ||||
|         bit_cnt+=n; | ||||
|     } else { | ||||
|         bit_buf |= value << (bit_cnt); | ||||
|  | ||||
|         *s->buf_ptr = bit_buf & 0xff; | ||||
|         s->buf_ptr[1] = (bit_buf >> 8) & 0xff; | ||||
|         s->buf_ptr[2] = (bit_buf >> 16) & 0xff; | ||||
|         s->buf_ptr[3] = (bit_buf >> 24) & 0xff; | ||||
|  | ||||
|         //printf("bitbuf = %08x\n", bit_buf); | ||||
|         s->buf_ptr+=4; | ||||
|         if (s->buf_ptr >= s->buf_end) | ||||
|             puts("bit buffer overflow !!"); // should never happen ! who got rid of the callback ??? | ||||
| //            flush_buffer_rev(s); | ||||
|         bit_cnt=bit_cnt + n - 32; | ||||
|         if (bit_cnt == 0) { | ||||
|             bit_buf = 0; | ||||
|         } else { | ||||
|             bit_buf = value >> (n - bit_cnt); | ||||
|         } | ||||
|     } | ||||
|  | ||||
|     s->bit_buf = bit_buf; | ||||
|     s->bit_left = 32 - bit_cnt; | ||||
| } | ||||
|  | ||||
| /* pad the end of the output stream with zeros */ | ||||
| static void gif_flush_put_bits_rev(PutBitContext *s) | ||||
| { | ||||
|     while (s->bit_left < 32) { | ||||
|         /* XXX: should test end of buffer */ | ||||
|         *s->buf_ptr++=s->bit_buf & 0xff; | ||||
|         s->bit_buf>>=8; | ||||
|         s->bit_left+=8; | ||||
|     } | ||||
| //    flush_buffer_rev(s); | ||||
|     s->bit_left=32; | ||||
|     s->bit_buf=0; | ||||
| } | ||||
|  | ||||
| /* !RevPutBitContext */ | ||||
|  | ||||
| /* GIF header */ | ||||
| static int gif_image_write_header(uint8_t **bytestream, | ||||
|                                   int width, int height, int loop_count, | ||||
|                                   uint32_t *palette) | ||||
| { | ||||
|     int i; | ||||
|     unsigned int v; | ||||
|  | ||||
|     bytestream_put_buffer(bytestream, "GIF", 3); | ||||
|     bytestream_put_buffer(bytestream, "89a", 3); | ||||
|     bytestream_put_le16(bytestream, width); | ||||
|     bytestream_put_le16(bytestream, height); | ||||
|  | ||||
|     bytestream_put_byte(bytestream, 0xf7); /* flags: global clut, 256 entries */ | ||||
|     bytestream_put_byte(bytestream, 0x1f); /* background color index */ | ||||
|     bytestream_put_byte(bytestream, 0); /* aspect ratio */ | ||||
|  | ||||
|     /* the global palette */ | ||||
|     if (!palette) { | ||||
|         bytestream_put_buffer(bytestream, (const unsigned char *)gif_clut, 216*3); | ||||
|         for(i=0;i<((256-216)*3);i++) | ||||
|             bytestream_put_byte(bytestream, 0); | ||||
|     } else { | ||||
|         for(i=0;i<256;i++) { | ||||
|             v = palette[i]; | ||||
|             bytestream_put_byte(bytestream, (v >> 16) & 0xff); | ||||
|             bytestream_put_byte(bytestream, (v >> 8) & 0xff); | ||||
|             bytestream_put_byte(bytestream, (v) & 0xff); | ||||
|         } | ||||
|     } | ||||
|  | ||||
|         /*        update: this is the 'NETSCAPE EXTENSION' that allows for looped animated gif | ||||
|                 see http://members.aol.com/royalef/gifabout.htm#net-extension | ||||
|  | ||||
|                 byte   1       : 33 (hex 0x21) GIF Extension code | ||||
|                 byte   2       : 255 (hex 0xFF) Application Extension Label | ||||
|                 byte   3       : 11 (hex (0x0B) Length of Application Block | ||||
|                                          (eleven bytes of data to follow) | ||||
|                 bytes  4 to 11 : "NETSCAPE" | ||||
|                 bytes 12 to 14 : "2.0" | ||||
|                 byte  15       : 3 (hex 0x03) Length of Data Sub-Block | ||||
|                                          (three bytes of data to follow) | ||||
|                 byte  16       : 1 (hex 0x01) | ||||
|                 bytes 17 to 18 : 0 to 65535, an unsigned integer in | ||||
|                                          lo-hi byte format. This indicate the | ||||
|                                          number of iterations the loop should | ||||
|                                          be executed. | ||||
|                 bytes 19       : 0 (hex 0x00) a Data Sub-block Terminator | ||||
|         */ | ||||
|  | ||||
|     /* application extension header */ | ||||
| #ifdef GIF_ADD_APP_HEADER | ||||
|     if (loop_count >= 0 && loop_count <= 65535) { | ||||
|         bytestream_put_byte(bytestream, 0x21); | ||||
|         bytestream_put_byte(bytestream, 0xff); | ||||
|         bytestream_put_byte(bytestream, 0x0b); | ||||
|         bytestream_put_buffer(bytestream, "NETSCAPE2.0", 11);  // bytes 4 to 14 | ||||
|         bytestream_put_byte(bytestream, 0x03); // byte 15 | ||||
|         bytestream_put_byte(bytestream, 0x01); // byte 16 | ||||
|         bytestream_put_le16(bytestream, (uint16_t)loop_count); | ||||
|         bytestream_put_byte(bytestream, 0x00); // byte 19 | ||||
|     } | ||||
| #endif | ||||
|     return 0; | ||||
| } | ||||
|  | ||||
| /* this is maybe slow, but allows for extensions */ | ||||
| static inline unsigned char gif_clut_index(uint8_t r, uint8_t g, uint8_t b) | ||||
| { | ||||
|     return ((((r)/47)%6)*6*6+(((g)/47)%6)*6+(((b)/47)%6)); | ||||
| } | ||||
|  | ||||
|  | ||||
| static int gif_image_write_image(uint8_t **bytestream, | ||||
|                                  int x1, int y1, int width, int height, | ||||
|                                  const uint8_t *buf, int linesize, int pix_fmt) | ||||
| { | ||||
|     PutBitContext p; | ||||
|     uint8_t buffer[200]; /* 100 * 9 / 8 = 113 */ | ||||
|     int i, left, w, v; | ||||
|     const uint8_t *ptr; | ||||
|     /* image block */ | ||||
|  | ||||
|     bytestream_put_byte(bytestream, 0x2c); | ||||
|     bytestream_put_le16(bytestream, x1); | ||||
|     bytestream_put_le16(bytestream, y1); | ||||
|     bytestream_put_le16(bytestream, width); | ||||
|     bytestream_put_le16(bytestream, height); | ||||
|     bytestream_put_byte(bytestream, 0x00); /* flags */ | ||||
|     /* no local clut */ | ||||
|  | ||||
|     bytestream_put_byte(bytestream, 0x08); | ||||
|  | ||||
|     left= width * height; | ||||
|  | ||||
|     init_put_bits(&p, buffer, 130); | ||||
|  | ||||
| /* | ||||
|  * the thing here is the bitstream is written as little packets, with a size byte before | ||||
|  * but it's still the same bitstream between packets (no flush !) | ||||
|  */ | ||||
|     ptr = buf; | ||||
|     w = width; | ||||
|     while(left>0) { | ||||
|  | ||||
|         gif_put_bits_rev(&p, 9, 0x0100); /* clear code */ | ||||
|  | ||||
|         for(i=(left<GIF_CHUNKS)?left:GIF_CHUNKS;i;i--) { | ||||
|             if (pix_fmt == PIX_FMT_RGB24) { | ||||
|                 v = gif_clut_index(ptr[0], ptr[1], ptr[2]); | ||||
|                 ptr+=3; | ||||
|             } else { | ||||
|                 v = *ptr++; | ||||
|             } | ||||
|             gif_put_bits_rev(&p, 9, v); | ||||
|             if (--w == 0) { | ||||
|                 w = width; | ||||
|                 buf += linesize; | ||||
|                 ptr = buf; | ||||
|             } | ||||
|         } | ||||
|  | ||||
|         if(left<=GIF_CHUNKS) { | ||||
|             gif_put_bits_rev(&p, 9, 0x101); /* end of stream */ | ||||
|             gif_flush_put_bits_rev(&p); | ||||
|         } | ||||
|         if(pbBufPtr(&p) - p.buf > 0) { | ||||
|             bytestream_put_byte(bytestream, pbBufPtr(&p) - p.buf); /* byte count of the packet */ | ||||
|             bytestream_put_buffer(bytestream, p.buf, pbBufPtr(&p) - p.buf); /* the actual buffer */ | ||||
|             p.buf_ptr = p.buf; /* dequeue the bytes off the bitstream */ | ||||
|         } | ||||
|         left-=GIF_CHUNKS; | ||||
|     } | ||||
|     bytestream_put_byte(bytestream, 0x00); /* end of image block */ | ||||
|     bytestream_put_byte(bytestream, 0x3b); | ||||
|     return 0; | ||||
| } | ||||
|  | ||||
| typedef struct { | ||||
|     int64_t time, file_time; | ||||
|     uint8_t buffer[100]; /* data chunks */ | ||||
|     AVFrame picture; | ||||
| } GIFContext; | ||||
|  | ||||
| static int gif_encode_init(AVCodecContext *avctx) | ||||
| { | ||||
|     GIFContext *s = avctx->priv_data; | ||||
|  | ||||
|     avctx->coded_frame = &s->picture; | ||||
|     return 0; | ||||
| } | ||||
|  | ||||
| /* better than nothing gif encoder */ | ||||
| static int gif_encode_frame(AVCodecContext *avctx, unsigned char *outbuf, int buf_size, void *data) | ||||
| { | ||||
|     GIFContext *s = avctx->priv_data; | ||||
|     AVFrame *pict = data; | ||||
|     AVFrame *const p = (AVFrame *)&s->picture; | ||||
|     uint8_t *outbuf_ptr = outbuf; | ||||
|  | ||||
|     *p = *pict; | ||||
|     p->pict_type = FF_I_TYPE; | ||||
|     p->key_frame = 1; | ||||
|     gif_image_write_header(&outbuf_ptr, avctx->width, avctx->height, -1, (uint32_t *)pict->data[1]); | ||||
|     gif_image_write_image(&outbuf_ptr, 0, 0, avctx->width, avctx->height, pict->data[0], pict->linesize[0], PIX_FMT_PAL8); | ||||
|     return outbuf_ptr - outbuf; | ||||
| } | ||||
|  | ||||
| AVCodec gif_encoder = { | ||||
|     "gif", | ||||
|     CODEC_TYPE_VIDEO, | ||||
|     CODEC_ID_GIF, | ||||
|     sizeof(GIFContext), | ||||
|     gif_encode_init, | ||||
|     gif_encode_frame, | ||||
|     NULL, //encode_end, | ||||
|     .pix_fmts= (enum PixelFormat[]){PIX_FMT_PAL8, -1}, | ||||
| }; | ||||
		Reference in New Issue
	
	Block a user