mirror of
https://git.ffmpeg.org/ffmpeg.git
synced 2024-12-25 16:52:31 +00:00
7a72695c05
* commit '36ef5369ee9b336febc2c270f8718cec4476cb85': Replace all CODEC_ID_* with AV_CODEC_ID_* lavc: add AV prefix to codec ids. Conflicts: doc/APIchanges doc/examples/decoding_encoding.c doc/examples/muxing.c ffmpeg.c ffprobe.c ffserver.c libavcodec/8svx.c libavcodec/avcodec.h libavcodec/dnxhd_parser.c libavcodec/dvdsubdec.c libavcodec/error_resilience.c libavcodec/h263dec.c libavcodec/libvorbisenc.c libavcodec/mjpeg_parser.c libavcodec/mjpegenc.c libavcodec/mpeg12.c libavcodec/mpeg4videodec.c libavcodec/mpegvideo.c libavcodec/mpegvideo_enc.c libavcodec/pcm.c libavcodec/r210dec.c libavcodec/utils.c libavcodec/v210dec.c libavcodec/version.h libavdevice/alsa-audio-dec.c libavdevice/bktr.c libavdevice/v4l2.c libavformat/asfdec.c libavformat/asfenc.c libavformat/avformat.h libavformat/avidec.c libavformat/caf.c libavformat/electronicarts.c libavformat/flacdec.c libavformat/flvdec.c libavformat/flvenc.c libavformat/framecrcenc.c libavformat/img2.c libavformat/img2dec.c libavformat/img2enc.c libavformat/ipmovie.c libavformat/isom.c libavformat/matroska.c libavformat/matroskadec.c libavformat/matroskaenc.c libavformat/mov.c libavformat/movenc.c libavformat/mp3dec.c libavformat/mpeg.c libavformat/mpegts.c libavformat/mxf.c libavformat/mxfdec.c libavformat/mxfenc.c libavformat/nsvdec.c libavformat/nut.c libavformat/oggenc.c libavformat/pmpdec.c libavformat/rawdec.c libavformat/rawenc.c libavformat/riff.c libavformat/sdp.c libavformat/utils.c libavformat/vocenc.c libavformat/wtv.c libavformat/xmv.c Merged-by: Michael Niedermayer <michaelni@gmx.at>
213 lines
6.7 KiB
C
213 lines
6.7 KiB
C
/*
|
|
* 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 "internal.h"
|
|
#include "lzw.h"
|
|
|
|
/* The GIF format uses reversed order for bitstreams... */
|
|
/* at least they don't use PDP_ENDIAN :) */
|
|
#define BITSTREAM_WRITER_LE
|
|
|
|
#include "put_bits.h"
|
|
|
|
typedef struct {
|
|
AVFrame picture;
|
|
LZWState *lzw;
|
|
uint8_t *buf;
|
|
} GIFContext;
|
|
|
|
/* GIF header */
|
|
static int gif_image_write_header(AVCodecContext *avctx,
|
|
uint8_t **bytestream, uint32_t *palette)
|
|
{
|
|
int i;
|
|
unsigned int v, smallest_alpha = 0xFF, alpha_component = 0;
|
|
|
|
bytestream_put_buffer(bytestream, "GIF", 3);
|
|
bytestream_put_buffer(bytestream, "89a", 3);
|
|
bytestream_put_le16(bytestream, avctx->width);
|
|
bytestream_put_le16(bytestream, avctx->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 */
|
|
for(i=0;i<256;i++) {
|
|
v = palette[i];
|
|
bytestream_put_be24(bytestream, v);
|
|
if (v >> 24 < smallest_alpha) {
|
|
smallest_alpha = v >> 24;
|
|
alpha_component = i;
|
|
}
|
|
}
|
|
|
|
if (smallest_alpha < 128) {
|
|
bytestream_put_byte(bytestream, 0x21); /* Extension Introducer */
|
|
bytestream_put_byte(bytestream, 0xf9); /* Graphic Control Label */
|
|
bytestream_put_byte(bytestream, 0x04); /* block length */
|
|
bytestream_put_byte(bytestream, 0x01); /* Transparent Color Flag */
|
|
bytestream_put_le16(bytestream, 0x00); /* no delay */
|
|
bytestream_put_byte(bytestream, alpha_component);
|
|
bytestream_put_byte(bytestream, 0x00);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int gif_image_write_image(AVCodecContext *avctx,
|
|
uint8_t **bytestream, uint8_t *end,
|
|
const uint8_t *buf, int linesize)
|
|
{
|
|
GIFContext *s = avctx->priv_data;
|
|
int len = 0, height;
|
|
const uint8_t *ptr;
|
|
/* image block */
|
|
|
|
bytestream_put_byte(bytestream, 0x2c);
|
|
bytestream_put_le16(bytestream, 0);
|
|
bytestream_put_le16(bytestream, 0);
|
|
bytestream_put_le16(bytestream, avctx->width);
|
|
bytestream_put_le16(bytestream, avctx->height);
|
|
bytestream_put_byte(bytestream, 0x00); /* flags */
|
|
/* no local clut */
|
|
|
|
bytestream_put_byte(bytestream, 0x08);
|
|
|
|
ff_lzw_encode_init(s->lzw, s->buf, avctx->width*avctx->height,
|
|
12, FF_LZW_GIF, put_bits);
|
|
|
|
ptr = buf;
|
|
for (height = avctx->height; height--;) {
|
|
len += ff_lzw_encode(s->lzw, ptr, avctx->width);
|
|
ptr += linesize;
|
|
}
|
|
len += ff_lzw_encode_flush(s->lzw, flush_put_bits);
|
|
|
|
ptr = s->buf;
|
|
while (len > 0) {
|
|
int size = FFMIN(255, len);
|
|
bytestream_put_byte(bytestream, size);
|
|
if (end - *bytestream < size)
|
|
return -1;
|
|
bytestream_put_buffer(bytestream, ptr, size);
|
|
ptr += size;
|
|
len -= size;
|
|
}
|
|
bytestream_put_byte(bytestream, 0x00); /* end of image block */
|
|
bytestream_put_byte(bytestream, 0x3b);
|
|
return 0;
|
|
}
|
|
|
|
static av_cold int gif_encode_init(AVCodecContext *avctx)
|
|
{
|
|
GIFContext *s = avctx->priv_data;
|
|
|
|
if (avctx->width > 65535 || avctx->height > 65535) {
|
|
av_log(avctx, AV_LOG_ERROR, "GIF does not support resolutions above 65535x65535\n");
|
|
return -1;
|
|
}
|
|
|
|
avctx->coded_frame = &s->picture;
|
|
s->lzw = av_mallocz(ff_lzw_encode_state_size);
|
|
if (!s->lzw)
|
|
return AVERROR(ENOMEM);
|
|
s->buf = av_malloc(avctx->width*avctx->height*2);
|
|
if (!s->buf)
|
|
return AVERROR(ENOMEM);
|
|
return 0;
|
|
}
|
|
|
|
/* better than nothing gif encoder */
|
|
static int gif_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
|
|
const AVFrame *pict, int *got_packet)
|
|
{
|
|
GIFContext *s = avctx->priv_data;
|
|
AVFrame *const p = &s->picture;
|
|
uint8_t *outbuf_ptr, *end;
|
|
int ret;
|
|
|
|
if ((ret = ff_alloc_packet2(avctx, pkt, avctx->width*avctx->height*7/5 + FF_MIN_BUFFER_SIZE)) < 0)
|
|
return ret;
|
|
outbuf_ptr = pkt->data;
|
|
end = pkt->data + pkt->size;
|
|
|
|
*p = *pict;
|
|
p->pict_type = AV_PICTURE_TYPE_I;
|
|
p->key_frame = 1;
|
|
gif_image_write_header(avctx, &outbuf_ptr, (uint32_t *)pict->data[1]);
|
|
gif_image_write_image(avctx, &outbuf_ptr, end, pict->data[0], pict->linesize[0]);
|
|
|
|
pkt->size = outbuf_ptr - pkt->data;
|
|
pkt->flags |= AV_PKT_FLAG_KEY;
|
|
*got_packet = 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int gif_encode_close(AVCodecContext *avctx)
|
|
{
|
|
GIFContext *s = avctx->priv_data;
|
|
|
|
av_freep(&s->lzw);
|
|
av_freep(&s->buf);
|
|
return 0;
|
|
}
|
|
|
|
AVCodec ff_gif_encoder = {
|
|
.name = "gif",
|
|
.type = AVMEDIA_TYPE_VIDEO,
|
|
.id = AV_CODEC_ID_GIF,
|
|
.priv_data_size = sizeof(GIFContext),
|
|
.init = gif_encode_init,
|
|
.encode2 = gif_encode_frame,
|
|
.close = gif_encode_close,
|
|
.pix_fmts = (const enum PixelFormat[]){
|
|
PIX_FMT_RGB8, PIX_FMT_BGR8, PIX_FMT_RGB4_BYTE, PIX_FMT_BGR4_BYTE,
|
|
PIX_FMT_GRAY8, PIX_FMT_PAL8, PIX_FMT_NONE
|
|
},
|
|
.long_name = NULL_IF_CONFIG_SMALL("GIF (Graphics Interchange Format)"),
|
|
};
|