@@ -64,6 +64,7 @@ version <next>

 - Tiertex .seq demuxer/video decoder

 - MTV demuxer

 - TIFF picture decoder

+- GIF picture decoder

 version 0.4.9-pre1:

@@ -121,6 +121,7 @@ Codecs:

   flashsv.c                             Benjamin Larsson

   flicvideo.c                           Mike Melanson

   g726.c                                Roman Shaposhnik

+  gifdec.c                              Baptiste Coudurier

   h264*                                 Loren Merritt, Michael Niedermayer

   h261*                                 Michael Niedermayer

   h263*                                 Michael Niedermayer

@@ -84,6 +84,7 @@ OBJS-$(CONFIG_FLASHSV_DECODER)         += flashsv.o

 OBJS-$(CONFIG_FLIC_DECODER)            += flicvideo.o

 OBJS-$(CONFIG_FOURXM_DECODER)          += 4xm.o

 OBJS-$(CONFIG_FRAPS_DECODER)           += fraps.o

+OBJS-$(CONFIG_GIF_DECODER)             += gifdec.o

 OBJS-$(CONFIG_H261_DECODER)            += h261.o

 OBJS-$(CONFIG_H261_ENCODER)            += h261.o

 OBJS-$(CONFIG_H264_DECODER)            += h264.o

@@ -193,6 +193,9 @@ void avcodec_register_all(void)

 #endif //CONFIG_RAWVIDEO_ENCODER

     /* decoders */

+#ifdef CONFIG_GIF_DECODER

+    register_avcodec(&gif_decoder);

+#endif

 #ifdef CONFIG_H263_DECODER

     register_avcodec(&h263_decoder);

 #endif //CONFIG_H263_DECODER

@@ -37,8 +37,8 @@ extern "C" {

 #define AV_STRINGIFY(s)         AV_TOSTRING(s)

 #define AV_TOSTRING(s) #s

-#define LIBAVCODEC_VERSION_INT  ((51<<16)+(20<<8)+0)

-#define LIBAVCODEC_VERSION      51.20.0

+#define LIBAVCODEC_VERSION_INT  ((51<<16)+(21<<8)+0)

+#define LIBAVCODEC_VERSION      51.21.0

 #define LIBAVCODEC_BUILD        LIBAVCODEC_VERSION_INT

 #define LIBAVCODEC_IDENT        "Lavc" AV_STRINGIFY(LIBAVCODEC_VERSION)

@@ -148,6 +148,7 @@ enum CodecID {

     CODEC_ID_DSICINVIDEO,

     CODEC_ID_TIERTEXSEQVIDEO,

     CODEC_ID_TIFF,

+    CODEC_ID_GIF,

     /* various pcm "codecs" */

     CODEC_ID_PCM_S16LE= 0x10000,

@@ -2177,6 +2178,7 @@ extern AVCodec sonic_ls_encoder;

 extern AVCodec svq1_encoder;

 extern AVCodec x264_encoder;

+extern AVCodec gif_decoder;

 extern AVCodec h263_decoder;

 extern AVCodec h261_decoder;

 extern AVCodec mpeg4_decoder;

new file mode 100644

@@ -0,0 +1,50 @@

+/*

+ * Bytestream functions

+ * copyright (c) 2006 Baptiste Coudurier <baptiste.coudurier@free.fr>

+ *

+ * 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

+ */

+

+#ifndef FFMPEG_BYTESTREAM_H

+#define FFMPEG_BYTESTREAM_H

+

+static always_inline unsigned int bytestream_get_le32(uint8_t **b)

+{

+    (*b) += 4;

+    return LE_32(*b - 4);

+}

+

+static always_inline unsigned int bytestream_get_le16(uint8_t **b)

+{

+    (*b) += 2;

+    return LE_16(*b - 2);

+}

+

+static always_inline unsigned int bytestream_get_byte(uint8_t **b)

+{

+    (*b)++;

+    return (*b)[-1];

+}

+

+static always_inline unsigned int bytestream_get_buffer(uint8_t **b, uint8_t *dst, unsigned int size)

+{

+    memcpy(dst, *b, size);

+    (*b) += size;

+    return size;

+}

+

+#endif /* FFMPEG_BYTESTREAM_H */

new file mode 100644

@@ -0,0 +1,495 @@

+/*

+ * GIF decoder

+ * Copyright (c) 2003 Fabrice Bellard.

+ * 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

+ */

+

+//#define DEBUG

+

+#include "avcodec.h"

+#include "bytestream.h"

+

+#define MAXBITS                 12

+#define         SIZTABLE        (1<<MAXBITS)

+

+#define GCE_DISPOSAL_NONE       0

+#define GCE_DISPOSAL_INPLACE    1

+#define GCE_DISPOSAL_BACKGROUND 2

+#define GCE_DISPOSAL_RESTORE    3

+

+typedef struct GifState {

+    int screen_width;

+    int screen_height;

+    int bits_per_pixel;

+    int background_color_index;

+    int transparent_color_index;

+    int color_resolution;

+    uint8_t *image_buf;

+    int image_linesize;

+    uint32_t image_palette[256];

+    int pix_fmt;

+

+    /* after the frame is displayed, the disposal method is used */

+    int gce_disposal;

+    /* delay during which the frame is shown */

+    int gce_delay;

+

+    /* LZW compatible decoder */

+    uint8_t *bytestream;

+    int eob_reached;

+    uint8_t *pbuf, *ebuf;

+    int bbits;

+    unsigned int bbuf;

+

+    int cursize;                /* The current code size */

+    int curmask;

+    int codesize;

+    int clear_code;

+    int end_code;

+    int newcodes;               /* First available code */

+    int top_slot;               /* Highest code for current size */

+    int slot;                   /* Last read code */

+    int fc, oc;

+    uint8_t *sp;

+    uint8_t stack[SIZTABLE];

+    uint8_t suffix[SIZTABLE];

+    uint16_t prefix[SIZTABLE];

+

+    /* aux buffers */

+    uint8_t global_palette[256 * 3];

+    uint8_t local_palette[256 * 3];

+    uint8_t buf[256];

+} GifState;

+

+static const uint8_t gif87a_sig[6] = "GIF87a";

+static const uint8_t gif89a_sig[6] = "GIF89a";

+

+static const uint16_t mask[17] =

+{

+    0x0000, 0x0001, 0x0003, 0x0007,

+    0x000F, 0x001F, 0x003F, 0x007F,

+    0x00FF, 0x01FF, 0x03FF, 0x07FF,

+    0x0FFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF

+};

+

+static void GLZWDecodeInit(GifState * s, int csize)

+{

+    /* read buffer */

+    s->eob_reached = 0;

+    s->pbuf = s->buf;

+    s->ebuf = s->buf;

+    s->bbuf = 0;

+    s->bbits = 0;

+

+    /* decoder */

+    s->codesize = csize;

+    s->cursize = s->codesize + 1;

+    s->curmask = mask[s->cursize];

+    s->top_slot = 1 << s->cursize;

+    s->clear_code = 1 << s->codesize;

+    s->end_code = s->clear_code + 1;

+    s->slot = s->newcodes = s->clear_code + 2;

+    s->oc = s->fc = 0;

+    s->sp = s->stack;

+}

+

+/* XXX: optimize */

+static inline int GetCode(GifState * s)

+{

+    int c, sizbuf;

+    uint8_t *ptr;

+

+    while (s->bbits < s->cursize) {

+        ptr = s->pbuf;

+        if (ptr >= s->ebuf) {

+            if (!s->eob_reached) {

+                sizbuf = bytestream_get_byte(&s->bytestream);

+                s->ebuf = s->buf + sizbuf;

+                s->pbuf = s->buf;

+                if (sizbuf > 0) {

+                    bytestream_get_buffer(&s->bytestream, s->buf, sizbuf);

+                } else {

+                    s->eob_reached = 1;

+                }

+            }

+            ptr = s->pbuf;

+        }

+        s->bbuf |= ptr[0] << s->bbits;

+        ptr++;

+        s->pbuf = ptr;

+        s->bbits += 8;

+    }

+    c = s->bbuf & s->curmask;

+    s->bbuf >>= s->cursize;

+    s->bbits -= s->cursize;

+    return c;

+}

+

+/* NOTE: the algorithm here is inspired from the LZW GIF decoder

+   written by Steven A. Bennett in 1987. */

+/* return the number of byte decoded */

+static int GLZWDecode(GifState * s, uint8_t * buf, int len)

+{

+    int l, c, code, oc, fc;

+    uint8_t *sp;

+

+    if (s->end_code < 0)

+        return 0;

+

+    l = len;

+    sp = s->sp;

+    oc = s->oc;

+    fc = s->fc;

+

+    while (sp > s->stack) {

+        *buf++ = *(--sp);

+        if ((--l) == 0)

+            goto the_end;

+    }

+

+    for (;;) {

+        c = GetCode(s);

+        if (c == s->end_code) {

+            s->end_code = -1;

+            break;

+        } else if (c == s->clear_code) {

+            s->cursize = s->codesize + 1;

+            s->curmask = mask[s->cursize];

+            s->slot = s->newcodes;

+            s->top_slot = 1 << s->cursize;

+            while ((c = GetCode(s)) == s->clear_code);

+            if (c == s->end_code) {

+                s->end_code = -1;

+                break;

+            }

+            /* test error */

+            if (c >= s->slot)

+                c = 0;

+            fc = oc = c;

+            *buf++ = c;

+            if ((--l) == 0)

+                break;

+        } else {

+            code = c;

+            if (code >= s->slot) {

+                *sp++ = fc;

+                code = oc;

+            }

+            while (code >= s->newcodes) {

+                *sp++ = s->suffix[code];

+                code = s->prefix[code];

+            }

+            *sp++ = code;

+            if (s->slot < s->top_slot) {

+                s->suffix[s->slot] = fc = code;

+                s->prefix[s->slot++] = oc;

+                oc = c;

+            }

+            if (s->slot >= s->top_slot) {

+                if (s->cursize < MAXBITS) {

+                    s->top_slot <<= 1;

+                    s->curmask = mask[++s->cursize];

+                }

+            }

+            while (sp > s->stack) {

+                *buf++ = *(--sp);

+                if ((--l) == 0)

+                    goto the_end;

+            }

+        }

+    }

+  the_end:

+    s->sp = sp;

+    s->oc = oc;

+    s->fc = fc;

+    return len - l;

+}

+

+static int gif_read_image(GifState *s)

+{

+    int left, top, width, height, bits_per_pixel, code_size, flags;

+    int is_interleaved, has_local_palette, y, x, pass, y1, linesize, n, i;

+    uint8_t *ptr, *line, *d, *spal, *palette, *sptr, *ptr1;

+

+    left = bytestream_get_le16(&s->bytestream);

+    top = bytestream_get_le16(&s->bytestream);

+    width = bytestream_get_le16(&s->bytestream);

+    height = bytestream_get_le16(&s->bytestream);

+    flags = bytestream_get_byte(&s->bytestream);

+    is_interleaved = flags & 0x40;

+    has_local_palette = flags & 0x80;

+    bits_per_pixel = (flags & 0x07) + 1;

+#ifdef DEBUG

+    printf("gif: image x=%d y=%d w=%d h=%d\n", left, top, width, height);

+#endif

+

+    if (has_local_palette) {

+        bytestream_get_buffer(&s->bytestream, s->local_palette, 3 * (1 << bits_per_pixel));

+        palette = s->local_palette;

+    } else {

+        palette = s->global_palette;

+        bits_per_pixel = s->bits_per_pixel;

+    }

+

+    /* verify that all the image is inside the screen dimensions */

+    if (left + width > s->screen_width ||

+        top + height > s->screen_height)

+        return -EINVAL;

+

+    /* build the palette */

+        n = (1 << bits_per_pixel);

+        spal = palette;

+        for(i = 0; i < n; i++) {

+            s->image_palette[i] = (0xff << 24) |

+                (spal[0] << 16) | (spal[1] << 8) | (spal[2]);

+            spal += 3;

+        }

+        for(; i < 256; i++)

+            s->image_palette[i] = (0xff << 24);

+        /* handle transparency */

+        if (s->transparent_color_index >= 0)

+            s->image_palette[s->transparent_color_index] = 0;

+        line = NULL;

+

+    /* now get the image data */

+    code_size = bytestream_get_byte(&s->bytestream);

+    GLZWDecodeInit(s, code_size);

+

+    /* read all the image */

+    linesize = s->image_linesize;

+    ptr1 = s->image_buf + top * linesize + (left * 3);

+    ptr = ptr1;

+    pass = 0;

+    y1 = 0;

+    for (y = 0; y < height; y++) {

+            GLZWDecode(s, ptr, width);

+        if (is_interleaved) {

+            switch(pass) {

+            default:

+            case 0:

+            case 1:

+                y1 += 8;

+                ptr += linesize * 8;

+                if (y1 >= height) {

+                    y1 = 4;

+                    if (pass == 0)

+                        ptr = ptr1 + linesize * 4;

+                    else

+                        ptr = ptr1 + linesize * 2;

+                    pass++;

+                }

+                break;

+            case 2:

+                y1 += 4;

+                ptr += linesize * 4;

+                if (y1 >= height) {

+                    y1 = 1;

+                    ptr = ptr1 + linesize;

+                    pass++;

+                }

+                break;

+            case 3:

+                y1 += 2;

+                ptr += linesize * 2;

+                break;

+            }

+        } else {

+            ptr += linesize;

+        }

+    }

+    av_free(line);

+

+    /* read the garbage data until end marker is found */

+    while (!s->eob_reached)

+        GetCode(s);

+    return 0;

+}

+

+static int gif_read_extension(GifState *s)

+{

+    int ext_code, ext_len, i, gce_flags, gce_transparent_index;

+

+    /* extension */

+    ext_code = bytestream_get_byte(&s->bytestream);

+    ext_len = bytestream_get_byte(&s->bytestream);

+#ifdef DEBUG

+    printf("gif: ext_code=0x%x len=%d\n", ext_code, ext_len);

+#endif

+    switch(ext_code) {

+    case 0xf9:

+        if (ext_len != 4)

+            goto discard_ext;

+        s->transparent_color_index = -1;

+        gce_flags = bytestream_get_byte(&s->bytestream);

+        s->gce_delay = bytestream_get_le16(&s->bytestream);

+        gce_transparent_index = bytestream_get_byte(&s->bytestream);

+        if (gce_flags & 0x01)

+            s->transparent_color_index = gce_transparent_index;

+        else

+            s->transparent_color_index = -1;

+        s->gce_disposal = (gce_flags >> 2) & 0x7;

+#ifdef DEBUG

+        printf("gif: gce_flags=%x delay=%d tcolor=%d disposal=%d\n",

+               gce_flags, s->gce_delay,

+               s->transparent_color_index, s->gce_disposal);

+#endif

+        ext_len = bytestream_get_byte(&s->bytestream);

+        break;

+    }

+

+    /* NOTE: many extension blocks can come after */

+ discard_ext:

+    while (ext_len != 0) {

+        for (i = 0; i < ext_len; i++)

+            bytestream_get_byte(&s->bytestream);

+        ext_len = bytestream_get_byte(&s->bytestream);

+#ifdef DEBUG

+        printf("gif: ext_len1=%d\n", ext_len);

+#endif

+    }

+    return 0;

+}

+

+static int gif_read_header1(GifState *s)

+{

+    uint8_t sig[6];

+    int ret, v, n;

+    int has_global_palette;

+

+    /* read gif signature */

+    bytestream_get_buffer(&s->bytestream, sig, 6);

+    if (memcmp(sig, gif87a_sig, 6) != 0 &&

+        memcmp(sig, gif89a_sig, 6) != 0)

+        return -1;

+

+    /* read screen header */

+    s->transparent_color_index = -1;

+    s->screen_width = bytestream_get_le16(&s->bytestream);

+    s->screen_height = bytestream_get_le16(&s->bytestream);

+    if(   (unsigned)s->screen_width  > 32767

+       || (unsigned)s->screen_height > 32767){

+        av_log(NULL, AV_LOG_ERROR, "picture size too large\n");

+        return -1;

+    }

+

+    v = bytestream_get_byte(&s->bytestream);

+    s->color_resolution = ((v & 0x70) >> 4) + 1;

+    has_global_palette = (v & 0x80);

+    s->bits_per_pixel = (v & 0x07) + 1;

+    s->background_color_index = bytestream_get_byte(&s->bytestream);

+    bytestream_get_byte(&s->bytestream);                /* ignored */

+#ifdef DEBUG

+    printf("gif: screen_w=%d screen_h=%d bpp=%d global_palette=%d\n",

+           s->screen_width, s->screen_height, s->bits_per_pixel,

+           has_global_palette);

+#endif

+    if (has_global_palette) {

+        n = 1 << s->bits_per_pixel;

+        bytestream_get_buffer(&s->bytestream, s->global_palette, n * 3);

+    }

+    return 0;

+}

+

+static int gif_parse_next_image(GifState *s)

+{

+    int ret, code;

+

+    for (;;) {

+        code = bytestream_get_byte(&s->bytestream);

+#ifdef DEBUG

+        printf("gif: code=%02x '%c'\n", code, code);

+#endif

+        switch (code) {

+        case ',':

+            if (gif_read_image(s) < 0)

+                return -1;

+            ret = 0;

+            goto the_end;

+        case ';':

+            /* end of image */

+            ret = -1;

+            goto the_end;

+        case '!':

+            if (gif_read_extension(s) < 0)

+                return -1;

+            break;

+        case EOF:

+        default:

+            /* error or errneous EOF */

+            ret = -1;

+            goto the_end;

+        }

+    }

+  the_end:

+    return ret;

+}

+

+static int gif_decode_init(AVCodecContext *avctx)

+{

+    GifState *s = avctx->priv_data;

+

+    return 0;

+}

+

+static int gif_decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8_t *buf, int buf_size)

+{

+    GifState *s = avctx->priv_data;

+    AVFrame *picture = data;

+    int ret;

+

+    s->bytestream = buf;

+    if (gif_read_header1(s) < 0)

+        return -1;

+

+    /* allocate image buffer */

+    s->image_linesize = s->screen_width * 3;

+    s->image_buf = av_malloc(s->screen_height * s->image_linesize);

+    if (!s->image_buf)

+        return -ENOMEM;

+    s->pix_fmt = PIX_FMT_PAL8;

+    /* now we are ready: build format streams */

+

+    /* XXX: check if screen size is always valid */

+    avctx->width = s->screen_width;

+    avctx->height = s->screen_height;

+    avctx->pix_fmt = PIX_FMT_PAL8;

+

+    ret = gif_parse_next_image(s);

+    if (ret < 0)

+        return ret;

+

+    picture->data[0] = s->image_buf;

+    picture->linesize[0] = s->image_linesize;

+    picture->data[1] = s->image_palette;

+    picture->linesize[1] = 4;

+

+    *data_size = sizeof(AVPicture);

+    return 0;

+}

+

+AVCodec gif_decoder = {

+    "gif",

+    CODEC_TYPE_VIDEO,

+    CODEC_ID_GIF,

+    sizeof(GifState),

+    gif_decode_init,

+    NULL,

+    NULL,

+    gif_decode_frame,

+};