X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fgif.c;h=a34d710a1074435cde8ba836ba228c273663c76a;hb=2caf19e90f270abe1e80a3e85acaf0eb5c9d0aac;hp=00a1bf4cc12633077de4a112527bd5f8a99e1c75;hpb=e4e8632aaf0d04145fc7133c271adbbbaefbc652;p=ffmpeg diff --git a/libavcodec/gif.c b/libavcodec/gif.c index 00a1bf4cc12..a34d710a107 100644 --- a/libavcodec/gif.c +++ b/libavcodec/gif.c @@ -4,20 +4,20 @@ * Copyright (c) 2002 Francois Revol * Copyright (c) 2006 Baptiste Coudurier * - * This file is part of FFmpeg. + * This file is part of Libav. * - * FFmpeg is free software; you can redistribute it and/or + * Libav 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, + * Libav 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 + * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ @@ -43,6 +43,7 @@ #include "avcodec.h" #include "bytestream.h" +#include "lzw.h" /* The GIF format uses reversed order for bitstreams... */ /* at least they don't use PDP_ENDIAN :) */ @@ -50,25 +51,23 @@ #include "put_bits.h" -/* bitstream minipacket size */ -#define GIF_CHUNKS 100 - typedef struct { AVFrame picture; + LZWState *lzw; + uint8_t *buf; } GIFContext; /* GIF header */ -static int gif_image_write_header(uint8_t **bytestream, - int width, int height, - uint32_t *palette) +static int gif_image_write_header(AVCodecContext *avctx, + uint8_t **bytestream, 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_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 */ @@ -83,59 +82,44 @@ static int gif_image_write_header(uint8_t **bytestream, return 0; } -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) +static int gif_image_write_image(AVCodecContext *avctx, + uint8_t **bytestream, uint8_t *end, + const uint8_t *buf, int linesize) { - PutBitContext p; - uint8_t buffer[200]; /* 100 * 9 / 8 = 113 */ - int i, left, w; + GIFContext *s = avctx->priv_data; + int len = 0, height; 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_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); - left= width * height; - - init_put_bits(&p, buffer, 130); + ff_lzw_encode_init(s->lzw, s->buf, avctx->width*avctx->height, + 12, FF_LZW_GIF, put_bits); -/* - * 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) { - - put_bits(&p, 9, 0x0100); /* clear code */ - - for(i=(left 0) { - bytestream_put_byte(bytestream, put_bits_ptr(&p) - p.buf); /* byte count of the packet */ - bytestream_put_buffer(bytestream, p.buf, put_bits_ptr(&p) - p.buf); /* the actual buffer */ - p.buf_ptr = p.buf; /* dequeue the bytes off the bitstream */ - } - left-=GIF_CHUNKS; + 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); @@ -147,6 +131,12 @@ static av_cold int gif_encode_init(AVCodecContext *avctx) GIFContext *s = avctx->priv_data; 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; } @@ -157,23 +147,33 @@ static int gif_encode_frame(AVCodecContext *avctx, unsigned char *outbuf, int bu AVFrame *pict = data; AVFrame *const p = (AVFrame *)&s->picture; uint8_t *outbuf_ptr = outbuf; + uint8_t *end = outbuf + buf_size; *p = *pict; - p->pict_type = FF_I_TYPE; + p->pict_type = AV_PICTURE_TYPE_I; p->key_frame = 1; - gif_image_write_header(&outbuf_ptr, avctx->width, avctx->height, (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); + 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]); return outbuf_ptr - outbuf; } -AVCodec gif_encoder = { +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 = { "gif", - CODEC_TYPE_VIDEO, + AVMEDIA_TYPE_VIDEO, CODEC_ID_GIF, sizeof(GIFContext), gif_encode_init, gif_encode_frame, - NULL, //encode_end, + 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)"), };