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-rw-r--r--contrib/ffmpeg/libavformat/gif.c419
1 files changed, 419 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavformat/gif.c b/contrib/ffmpeg/libavformat/gif.c
new file mode 100644
index 000000000..1083710d5
--- /dev/null
+++ b/contrib/ffmpeg/libavformat/gif.c
@@ -0,0 +1,419 @@
+/*
+ * Animated GIF muxer
+ * Copyright (c) 2000 Fabrice Bellard.
+ *
+ * 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 "avformat.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(ByteIOContext *pb,
+ int width, int height, int loop_count,
+ uint32_t *palette)
+{
+ int i;
+ unsigned int v;
+
+ put_tag(pb, "GIF");
+ put_tag(pb, "89a");
+ put_le16(pb, width);
+ put_le16(pb, height);
+
+ put_byte(pb, 0xf7); /* flags: global clut, 256 entries */
+ put_byte(pb, 0x1f); /* background color index */
+ put_byte(pb, 0); /* aspect ratio */
+
+ /* the global palette */
+ if (!palette) {
+ put_buffer(pb, (const unsigned char *)gif_clut, 216*3);
+ for(i=0;i<((256-216)*3);i++)
+ put_byte(pb, 0);
+ } else {
+ for(i=0;i<256;i++) {
+ v = palette[i];
+ put_byte(pb, (v >> 16) & 0xff);
+ put_byte(pb, (v >> 8) & 0xff);
+ put_byte(pb, (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) {
+ put_byte(pb, 0x21);
+ put_byte(pb, 0xff);
+ put_byte(pb, 0x0b);
+ 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;
+}
+
+/* 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(ByteIOContext *pb,
+ 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 */
+
+ put_byte(pb, 0x2c);
+ put_le16(pb, x1);
+ put_le16(pb, y1);
+ put_le16(pb, width);
+ put_le16(pb, height);
+ put_byte(pb, 0x00); /* flags */
+ /* no local clut */
+
+ put_byte(pb, 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) {
+ 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.buf_ptr = p.buf; /* dequeue the bytes off the bitstream */
+ }
+ left-=GIF_CHUNKS;
+ }
+ put_byte(pb, 0x00); /* end of image block */
+
+ return 0;
+}
+
+typedef struct {
+ int64_t time, file_time;
+ uint8_t buffer[100]; /* data chunks */
+} GIFContext;
+
+static int gif_write_header(AVFormatContext *s)
+{
+ GIFContext *gif = s->priv_data;
+ ByteIOContext *pb = &s->pb;
+ AVCodecContext *enc, *video_enc;
+ int i, width, height, loop_count /*, rate*/;
+
+/* XXX: do we reject audio streams or just ignore them ?
+ if(s->nb_streams > 1)
+ return -1;
+*/
+ gif->time = 0;
+ gif->file_time = 0;
+
+ video_enc = NULL;
+ for(i=0;i<s->nb_streams;i++) {
+ enc = s->streams[i]->codec;
+ if (enc->codec_type != CODEC_TYPE_AUDIO)
+ video_enc = enc;
+ }
+
+ if (!video_enc) {
+ av_free(gif);
+ return -1;
+ } else {
+ width = video_enc->width;
+ height = video_enc->height;
+ loop_count = s->loop_output;
+// rate = video_enc->time_base.den;
+ }
+
+ 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_IO;
+ }
+
+ gif_image_write_header(pb, width, height, loop_count, NULL);
+
+ put_flush_packet(&s->pb);
+ return 0;
+}
+
+static int gif_write_video(AVFormatContext *s,
+ AVCodecContext *enc, const uint8_t *buf, int size)
+{
+ ByteIOContext *pb = &s->pb;
+ GIFContext *gif = s->priv_data;
+ int jiffies;
+ int64_t delay;
+
+ /* graphic control extension block */
+ put_byte(pb, 0x21);
+ 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;
+
+ /* 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->time_base.num/enc->time_base.den) - 1;
+
+ put_le16(pb, jiffies);
+
+ put_byte(pb, 0x1f); /* transparent color index */
+ put_byte(pb, 0x00);
+
+ gif_image_write_image(pb, 0, 0, enc->width, enc->height,
+ buf, enc->width * 3, PIX_FMT_RGB24);
+
+ put_flush_packet(&s->pb);
+ return 0;
+}
+
+static int gif_write_packet(AVFormatContext *s, AVPacket *pkt)
+{
+ 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, 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;
+}
+
+AVOutputFormat gif_muxer = {
+ "gif",
+ "GIF Animation",
+ "image/gif",
+ "gif",
+ sizeof(GIFContext),
+ CODEC_ID_NONE,
+ CODEC_ID_RAWVIDEO,
+ gif_write_header,
+ gif_write_packet,
+ gif_write_trailer,
+};
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