* support for .au .gif .mov .mp4 by François Revol <revol@free.fr>

  hmm any opinions about GIF support ?

Originally committed as revision 385 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 404 insertions, 0 deletions

diff --git a/libav/gif.c b/libav/gif.c
new file mode 100644
index 0000000000..50486586ad
--- /dev/null
+++ b/libav/gif.c
@@ -0,0 +1,404 @@
+/*
+ * Animated GIF encoder
+ * Copyright (c) 2000 Gerard Lantau.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, 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"
+
+/* bitstream minipacket size */
+#define GIF_CHUNKS 100
+
+/* slows down the decoding (and some browsers doesn't like it) */
+/* #define GIF_ADD_APP_HEADER */
+
+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
+ */
+
+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
+
+void init_put_bits_rev(PutBitContext *s,
+                   UINT8 *buffer, int buffer_size,
+                   void *opaque,
+                   void (*write_data)(void *, UINT8 *, int))
+{
+    init_put_bits(s, buffer, buffer_size, opaque, write_data);
+}
+
+void 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;
+}
+
+/* return the number of bits output */
+INT64 get_bit_count_rev(PutBitContext *s)
+{
+    return get_bit_count(s);
+}
+
+void align_put_bits_rev(PutBitContext *s)
+{
+    align_put_bits(s);
+}
+
+/* pad the end of the output stream with zeros */
+void 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 */
+
+typedef struct {
+    UINT8 buffer[100]; /* data chunks */
+    INT64 time, file_time;
+} GIFContext;
+
+static int gif_write_header(AVFormatContext *s)
+{
+    GIFContext *gif;
+    ByteIOContext *pb = &s->pb;
+    AVCodecContext *enc, *video_enc;
+    int i, width, height, rate;
+
+/* XXX: do we reject audio streams or just ignore them ?
+    if(s->nb_streams > 1)
+        return -1;
+*/
+
+    gif = malloc(sizeof(GIFContext));
+    if (!gif)
+        return -1;
+    s->priv_data = gif;
+
+    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) {
+        free(gif);
+        return -1;
+    } else {
+        width = video_enc->width;
+        height = video_enc->height;
+        rate = video_enc->frame_rate;
+    }
+
+    /* XXX: is it allowed ? seems to work so far... */
+    video_enc->pix_fmt = PIX_FMT_RGB24;
+
+    /* GIF header */
+
+    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 */
+
+    put_buffer(pb, (unsigned char *)gif_clut, 216*3);
+    for(i=0;i<((256-216)*3);i++)
+       put_byte(pb, 0);
+
+    /* application extension header */
+    /* XXX: not really sure what to put in here... */
+#ifdef GIF_ADD_APP_HEADER
+    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);
+#endif
+
+    put_flush_packet(&s->pb);
+    return 0;
+}
+
+/* this is maybe slow, but allows for extensions */
+static inline unsigned char gif_clut_index(rgb_triplet *clut, UINT8 r, UINT8 g, UINT8 b)
+{
+    return ((((r)/47)%6)*6*6+(((g)/47)%6)*6+(((b)/47)%6));
+}
+
+/* chunk writer callback */
+/* !!! XXX:deprecated
+static void gif_put_chunk(void *pbctx, UINT8 *buffer, int count)
+{
+    ByteIOContext *pb = (ByteIOContext *)pbctx;
+    put_byte(pb, (UINT8)count);
+    put_buffer(pb, buffer, count);
+}
+*/
+
+static int gif_write_video(AVFormatContext *s, 
+                           AVCodecContext *enc, UINT8 *buf, int size)
+{
+    ByteIOContext *pb = &s->pb;
+    GIFContext *gif = s->priv_data;
+    int i, left, jiffies;
+    INT64 delay;
+    PutBitContext p;
+    UINT8 buffer[200]; /* 100 * 9 / 8 = 113 */
+
+
+    /* 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*FRAME_RATE_BASE/enc->frame_rate) - 1;
+
+    put_le16(pb, jiffies);
+
+    put_byte(pb, 0x1f); /* transparent color index */
+    put_byte(pb, 0x00);
+
+    /* image block */
+
+    put_byte(pb, 0x2c);
+    put_le16(pb, 0);
+    put_le16(pb, 0);
+    put_le16(pb, enc->width);
+    put_le16(pb, enc->height);
+    put_byte(pb, 0x00); /* flags */
+    /* no local clut */
+
+    put_byte(pb, 0x08);
+
+    left=size/3;
+
+    /* XXX:deprecated */
+    /*init_put_bits_rev(&p, buffer, sizeof(buf), (void *)pb, gif_put_chunk); *//* mmm found a but in my code: s/sizeof(buf)/150/ */
+
+    init_put_bits_rev(&p, buffer, 130, NULL, NULL);
+
+/*
+ * 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 !)
+ */
+
+    while(left>0) {
+
+        put_bits_rev(&p, 9, 0x0100); /* clear code */
+
+        for(i=0;i<GIF_CHUNKS;i++) {
+            put_bits_rev(&p, 9, gif_clut_index(NULL, *buf, buf[1], buf[2]));
+            buf+=3;
+        }
+
+        if(left<=GIF_CHUNKS) {
+            put_bits_rev(&p, 9, 0x101); /* end of stream */
+            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.data_out_size += pbBufPtr(&p) - p.buf;
+            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_flush_packet(&s->pb);
+    return 0;
+}
+
+static int gif_write_packet(AVFormatContext *s, int stream_index, 
+                           UINT8 *buf, int size)
+{
+    AVCodecContext *codec = &s->streams[stream_index]->codec;
+    if (codec->codec_type == CODEC_TYPE_AUDIO)
+        return 0; /* just ignore audio */
+    else
+        return gif_write_video(s, codec, buf, size);
+}
+
+static int gif_write_trailer(AVFormatContext *s)
+{
+    GIFContext *gif = s->priv_data;
+    ByteIOContext *pb = &s->pb;
+
+    put_byte(pb, 0x3b);
+    put_flush_packet(&s->pb);
+
+    free(gif);
+    return 0;
+}
+
+AVFormat gif_format = {
+    "gif",
+    "GIF Animation",
+    "image/gif",
+    "gif",
+    CODEC_ID_NONE,
+    CODEC_ID_RAWVIDEO,
+    gif_write_header,
+    gif_write_packet,
+    gif_write_trailer,
+
+    NULL, /* read_header */
+    NULL, /* read_packet */
+    NULL, /* read_close */
+};
+