/*
- * GIF decoder
+ * GIF demuxer
* Copyright (c) 2003 Fabrice Bellard.
*
- * This library is free software; you can redistribute it and/or
+ * 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 of the License, or (at your option) any later version.
+ * version 2.1 of the License, or (at your option) any later version.
*
- * This library is distributed in the hope that it will be useful,
+ * 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 this library; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avformat.h"
-int gif_write(ByteIOContext *pb, AVImageInfo *info);
-
//#define DEBUG
-#define MAXBITS 12
-#define SIZTABLE (1<<MAXBITS)
+#define MAXBITS 12
+#define SIZTABLE (1<<MAXBITS)
#define GCE_DISPOSAL_NONE 0
#define GCE_DISPOSAL_INPLACE 1
int gce_disposal;
/* delay during which the frame is shown */
int gce_delay;
-
+
/* LZW compatible decoder */
ByteIOContext *f;
int eob_reached;
int bbits;
unsigned int bbuf;
- int cursize; /* The current code size */
+ 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 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];
int gce_flags, gce_disposal;
if (pd->buf_size < 24 ||
- memcmp(pd->buf, gif89a_sig, 6) != 0)
+ memcmp(pd->buf, gif89a_sig, 6) != 0)
return 0;
p_end = pd->buf + pd->buf_size;
p = pd->buf + 6;
return 0;
}
-static int gif_image_probe(AVProbeData * pd)
-{
- if (pd->buf_size >= 24 &&
- (memcmp(pd->buf, gif87a_sig, 6) == 0 ||
- memcmp(pd->buf, gif89a_sig, 6) == 0))
- return AVPROBE_SCORE_MAX - 1;
- else
- return 0;
-}
-
-
static void GLZWDecodeInit(GifState * s, int csize)
{
/* read buffer */
s->bbuf |= ptr[0] << s->bbits;
ptr++;
s->pbuf = ptr;
- s->bbits += 8;
+ s->bbits += 8;
}
c = s->bbuf & s->curmask;
s->bbuf >>= s->cursize;
fc = s->fc;
while (sp > s->stack) {
- *buf++ = *(--sp);
- if ((--l) == 0)
- goto the_end;
+ *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)
+ 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;
#endif
if (has_local_palette) {
- get_buffer(f, s->local_palette, 3 * (1 << bits_per_pixel));
+ get_buffer(f, 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;
+ return AVERROR(EINVAL);
/* build the palette */
if (s->pix_fmt == PIX_FMT_RGB24) {
line = av_malloc(width);
if (!line)
- return -ENOMEM;
+ return AVERROR(ENOMEM);
} else {
n = (1 << bits_per_pixel);
spal = palette;
for(i = 0; i < n; i++) {
- s->image_palette[i] = (0xff << 24) |
+ s->image_palette[i] = (0xff << 24) |
(spal[0] << 16) | (spal[1] << 8) | (spal[2]);
spal += 3;
}
ptr += linesize * 8;
if (y1 >= height) {
y1 = 4;
- if (pass == 0)
+ if (pass == 0)
ptr = ptr1 + linesize * 4;
else
ptr = ptr1 + linesize * 2;
}
}
av_free(line);
-
+
/* read the garbage data until end marker is found */
while (!s->eob_reached)
GetCode(s);
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,
+ 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 = get_byte(f);
break;
}
-
+
/* NOTE: many extension blocks can come after */
discard_ext:
while (ext_len != 0) {
/* read gif signature */
ret = get_buffer(f, sig, 6);
if (ret != 6)
- return -1;
+ return -1;
if (memcmp(sig, gif87a_sig, 6) != 0 &&
- memcmp(sig, gif89a_sig, 6) != 0)
- return -1;
+ memcmp(sig, gif89a_sig, 6) != 0)
+ return -1;
/* read screen header */
s->transparent_color_index = -1;
s->screen_width = get_le16(f);
s->screen_height = get_le16(f);
- if( (unsigned)s->screen_width > 32767
+ 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 = get_byte(f);
s->color_resolution = ((v & 0x70) >> 4) + 1;
has_global_palette = (v & 0x80);
s->bits_per_pixel = (v & 0x07) + 1;
s->background_color_index = get_byte(f);
- get_byte(f); /* ignored */
+ get_byte(f); /* 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);
+ s->screen_width, s->screen_height, s->bits_per_pixel,
+ has_global_palette);
#endif
if (has_global_palette) {
- n = 1 << s->bits_per_pixel;
- get_buffer(f, s->global_palette, n * 3);
+ n = 1 << s->bits_per_pixel;
+ get_buffer(f, s->global_palette, n * 3);
}
return 0;
}
int ret, code;
for (;;) {
- code = url_fgetc(f);
+ code = url_fgetc(f);
#ifdef DEBUG
- printf("gif: code=%02x '%c'\n", code, code);
+ printf("gif: code=%02x '%c'\n", code, code);
#endif
- switch (code) {
- case ',':
- if (gif_read_image(s) < 0)
- return AVERROR_IO;
- ret = 0;
- goto the_end;
- case ';':
- /* end of image */
- ret = AVERROR_IO;
- goto the_end;
- case '!':
+ switch (code) {
+ case ',':
+ if (gif_read_image(s) < 0)
+ return AVERROR_IO;
+ ret = 0;
+ goto the_end;
+ case ';':
+ /* end of image */
+ ret = AVERROR_IO;
+ goto the_end;
+ case '!':
if (gif_read_extension(s) < 0)
return AVERROR_IO;
- break;
- case EOF:
- default:
- /* error or errneous EOF */
- ret = AVERROR_IO;
- goto the_end;
- }
+ break;
+ case EOF:
+ default:
+ /* error or errneous EOF */
+ ret = AVERROR_IO;
+ goto the_end;
+ }
}
the_end:
return ret;
}
static int gif_read_header(AVFormatContext * s1,
- AVFormatParameters * ap)
+ AVFormatParameters * ap)
{
GifState *s = s1->priv_data;
ByteIOContext *f = &s1->pb;
s->f = f;
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;
+ return AVERROR(ENOMEM);
s->pix_fmt = PIX_FMT_RGB24;
/* now we are ready: build format streams */
st = av_new_stream(s1, 0);
if (!st)
- return -1;
+ return -1;
- st->codec.codec_type = CODEC_TYPE_VIDEO;
- st->codec.codec_id = CODEC_ID_RAWVIDEO;
- st->codec.time_base.den = 5;
- st->codec.time_base.num = 1;
+ st->codec->codec_type = CODEC_TYPE_VIDEO;
+ st->codec->codec_id = CODEC_ID_RAWVIDEO;
+ st->codec->time_base.den = 5;
+ st->codec->time_base.num = 1;
/* XXX: check if screen size is always valid */
- st->codec.width = s->screen_width;
- st->codec.height = s->screen_height;
- st->codec.pix_fmt = PIX_FMT_RGB24;
+ st->codec->width = s->screen_width;
+ st->codec->height = s->screen_height;
+ st->codec->pix_fmt = PIX_FMT_RGB24;
return 0;
}
static int gif_read_packet(AVFormatContext * s1,
- AVPacket * pkt)
+ AVPacket * pkt)
{
GifState *s = s1->priv_data;
int ret;
/* XXX: avoid copying */
if (av_new_packet(pkt, s->screen_width * s->screen_height * 3)) {
- return AVERROR_IO;
+ return AVERROR_IO;
}
pkt->stream_index = 0;
memcpy(pkt->data, s->image_buf, s->screen_width * s->screen_height * 3);
return 0;
}
-/* read gif as image */
-static int gif_read(ByteIOContext *f,
- int (*alloc_cb)(void *opaque, AVImageInfo *info), void *opaque)
-{
- GifState s1, *s = &s1;
- AVImageInfo info1, *info = &info1;
- int ret;
-
- memset(s, 0, sizeof(GifState));
- s->f = f;
- if (gif_read_header1(s) < 0)
- return -1;
- info->width = s->screen_width;
- info->height = s->screen_height;
- info->pix_fmt = PIX_FMT_PAL8;
- ret = alloc_cb(opaque, info);
- if (ret)
- return ret;
- s->image_buf = info->pict.data[0];
- s->image_linesize = info->pict.linesize[0];
- s->image_palette = (uint32_t *)info->pict.data[1];
-
- if (gif_parse_next_image(s) < 0)
- return -1;
- return 0;
-}
-
-AVInputFormat gif_iformat =
+AVInputFormat gif_demuxer =
{
"gif",
"gif format",
gif_read_packet,
gif_read_close,
};
-
-AVImageFormat gif_image_format = {
- "gif",
- "gif",
- gif_image_probe,
- gif_read,
- (1 << PIX_FMT_PAL8),
- gif_write,
-};