X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavformat%2Fgif.c;h=2b802a9dca019e47ee5caaa559f8cbde4ab0c153;hb=852e0ca555514eb103a662df4f104cd596ed7cdf;hp=e64bd51b15df0d705671eb75175decaa168c1dd5;hpb=117a5490bd57adcb0be3274222e89fc6c7107f8b;p=ffmpeg diff --git a/libavformat/gif.c b/libavformat/gif.c index e64bd51b15d..2b802a9dca0 100644 --- a/libavformat/gif.c +++ b/libavformat/gif.c @@ -1,20 +1,22 @@ /* - * Animated GIF encoder - * Copyright (c) 2000 Fabrice Bellard. + * Animated GIF muxer + * Copyright (c) 2000 Fabrice Bellard * - * This library is free software; you can redistribute it and/or + * 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 of the License, or (at your option) any later version. + * version 2.1 of the License, or (at your option) any later version. * - * This library is distributed in the hope that it will be useful, + * 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 this library; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /* @@ -39,11 +41,18 @@ #include "avformat.h" +/* The GIF format uses reversed order for bitstreams... */ +/* at least they don't use PDP_ENDIAN :) */ +#define BITSTREAM_WRITER_LE + +#include "libavcodec/put_bits.h" + /* bitstream minipacket size */ #define GIF_CHUNKS 100 -/* slows down the decoding (and some browsers doesn't like it) */ -/* #define GIF_ADD_APP_HEADER */ +/* 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; @@ -54,7 +63,7 @@ typedef struct { /* 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 + * 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 */ @@ -97,78 +106,10 @@ static const rgb_triplet gif_clut[216] = { { 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; - -#ifdef STATS - st_out_bit_counts[st_current_index] += n; -#endif - // 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(ByteIOContext *pb, - int width, int height, uint32_t *palette) +static int gif_image_write_header(ByteIOContext *pb, + int width, int height, int loop_count, + uint32_t *palette) { int i; unsigned int v; @@ -184,7 +125,7 @@ static int gif_image_write_header(ByteIOContext *pb, /* the global palette */ if (!palette) { - put_buffer(pb, (unsigned char *)gif_clut, 216*3); + put_buffer(pb, (const unsigned char *)gif_clut, 216*3); for(i=0;i<((256-216)*3);i++) put_byte(pb, 0); } else { @@ -196,17 +137,37 @@ static int gif_image_write_header(ByteIOContext *pb, } } + /* 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 */ - /* XXX: not really sure what to put in here... */ #ifdef GIF_ADD_APP_HEADER + if (loop_count >= 0 && loop_count <= 65535) { put_byte(pb, 0x21); put_byte(pb, 0xff); put_byte(pb, 0x0b); - put_tag(pb, "NETSCAPE2.0"); - put_byte(pb, 0x03); - put_byte(pb, 0x01); - put_byte(pb, 0x00); - put_byte(pb, 0x00); + put_tag(pb, "NETSCAPE2.0"); // bytes 4 to 14 + put_byte(pb, 0x03); // byte 15 + put_byte(pb, 0x01); // byte 16 + put_le16(pb, (uint16_t)loop_count); + put_byte(pb, 0x00); // byte 19 + } #endif return 0; } @@ -214,11 +175,11 @@ static int gif_image_write_header(ByteIOContext *pb, /* 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)); + return (((r) / 47) % 6) * 6 * 6 + (((g) / 47) % 6) * 6 + (((b) / 47) % 6); } -static int gif_image_write_image(ByteIOContext *pb, +static int gif_image_write_image(ByteIOContext *pb, int x1, int y1, int width, int height, const uint8_t *buf, int linesize, int pix_fmt) { @@ -250,16 +211,16 @@ static int gif_image_write_image(ByteIOContext *pb, w = width; while(left>0) { - gif_put_bits_rev(&p, 9, 0x0100); /* clear code */ + put_bits(&p, 9, 0x0100); /* clear code */ - for(i=0;i 0) { - put_byte(pb, pbBufPtr(&p) - p.buf); /* byte count of the packet */ - put_buffer(pb, p.buf, pbBufPtr(&p) - p.buf); /* the actual buffer */ - p.data_out_size += pbBufPtr(&p) - p.buf; + if(put_bits_ptr(&p) - p.buf > 0) { + put_byte(pb, put_bits_ptr(&p) - p.buf); /* byte count of the packet */ + put_buffer(pb, p.buf, put_bits_ptr(&p) - p.buf); /* the actual buffer */ p.buf_ptr = p.buf; /* dequeue the bytes off the bitstream */ } - if(left<=GIF_CHUNKS) { - put_byte(pb, 0x00); /* end of image block */ - } - left-=GIF_CHUNKS; } + put_byte(pb, 0x00); /* end of image block */ + return 0; } @@ -294,9 +252,9 @@ typedef struct { static int gif_write_header(AVFormatContext *s) { GIFContext *gif = s->priv_data; - ByteIOContext *pb = &s->pb; + ByteIOContext *pb = s->pb; AVCodecContext *enc, *video_enc; - int i, width, height/*, rate*/; + int i, width, height, loop_count /*, rate*/; /* XXX: do we reject audio streams or just ignore them ? if(s->nb_streams > 1) @@ -307,7 +265,7 @@ static int gif_write_header(AVFormatContext *s) video_enc = NULL; for(i=0;inb_streams;i++) { - enc = &s->streams[i]->codec; + enc = s->streams[i]->codec; if (enc->codec_type != CODEC_TYPE_AUDIO) video_enc = enc; } @@ -318,22 +276,25 @@ static int gif_write_header(AVFormatContext *s) } else { width = video_enc->width; height = video_enc->height; -// rate = video_enc->frame_rate; + loop_count = s->loop_output; +// rate = video_enc->time_base.den; } - /* XXX: is it allowed ? seems to work so far... */ - video_enc->pix_fmt = PIX_FMT_RGB24; + if (video_enc->pix_fmt != PIX_FMT_RGB24) { + av_log(s, AV_LOG_ERROR, "ERROR: gif only handles the rgb24 pixel format. Use -pix_fmt rgb24.\n"); + return AVERROR(EIO); + } - gif_image_write_header(pb, width, height, NULL); + gif_image_write_header(pb, width, height, loop_count, NULL); - put_flush_packet(&s->pb); + put_flush_packet(s->pb); return 0; } -static int gif_write_video(AVFormatContext *s, +static int gif_write_video(AVFormatContext *s, AVCodecContext *enc, const uint8_t *buf, int size) { - ByteIOContext *pb = &s->pb; + ByteIOContext *pb = s->pb; GIFContext *gif = s->priv_data; int jiffies; int64_t delay; @@ -343,7 +304,7 @@ static int gif_write_video(AVFormatContext *s, put_byte(pb, 0xf9); put_byte(pb, 0x04); /* block size */ put_byte(pb, 0x04); /* flags */ - + /* 1 jiffy is 1/70 s */ /* the delay_time field indicates the number of jiffies - 1 */ delay = gif->file_time - gif->time; @@ -351,7 +312,7 @@ static int gif_write_video(AVFormatContext *s, /* XXX: should use delay, in order to be more accurate */ /* instead of using the same rounded value each time */ /* XXX: don't even remember if I really use it for now */ - jiffies = (70*enc->frame_rate_base/enc->frame_rate) - 1; + jiffies = (70*enc->time_base.num/enc->time_base.den) - 1; put_le16(pb, jiffies); @@ -361,45 +322,31 @@ static int gif_write_video(AVFormatContext *s, gif_image_write_image(pb, 0, 0, enc->width, enc->height, buf, enc->width * 3, PIX_FMT_RGB24); - put_flush_packet(&s->pb); + put_flush_packet(s->pb); return 0; } -static int gif_write_packet(AVFormatContext *s, int stream_index, - const uint8_t *buf, int size, int64_t pts) +static int gif_write_packet(AVFormatContext *s, AVPacket *pkt) { - AVCodecContext *codec = &s->streams[stream_index]->codec; + AVCodecContext *codec = s->streams[pkt->stream_index]->codec; if (codec->codec_type == CODEC_TYPE_AUDIO) return 0; /* just ignore audio */ else - return gif_write_video(s, codec, buf, size); + return gif_write_video(s, codec, pkt->data, pkt->size); } static int gif_write_trailer(AVFormatContext *s) { - ByteIOContext *pb = &s->pb; - - put_byte(pb, 0x3b); - put_flush_packet(&s->pb); - return 0; -} + ByteIOContext *pb = s->pb; -/* better than nothing gif image writer */ -int gif_write(ByteIOContext *pb, AVImageInfo *info) -{ - gif_image_write_header(pb, info->width, info->height, - (uint32_t *)info->pict.data[1]); - gif_image_write_image(pb, 0, 0, info->width, info->height, - info->pict.data[0], info->pict.linesize[0], - PIX_FMT_PAL8); put_byte(pb, 0x3b); - put_flush_packet(pb); + put_flush_packet(s->pb); return 0; } -static AVOutputFormat gif_oformat = { +AVOutputFormat gif_muxer = { "gif", - "GIF Animation", + NULL_IF_CONFIG_SMALL("GIF Animation"), "image/gif", "gif", sizeof(GIFContext), @@ -409,12 +356,3 @@ static AVOutputFormat gif_oformat = { gif_write_packet, gif_write_trailer, }; - -extern AVInputFormat gif_iformat; - -int gif_init(void) -{ - av_register_output_format(&gif_oformat); - av_register_input_format(&gif_iformat); - return 0; -}