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/*
This file is part of libextractor.
(C) 2004, 2009 Vidyut Samanta and Christian Grothoff
libextractor 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, or (at your
option) any later version.
libextractor 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 libextractor; see the file COPYING. If not, write to the
Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.
This code was based on AVInfo 1.0 alpha 11
(c) George Shuklin, gs]AT[shounen.ru, 2002-2004
http://shounen.ru/soft/avinfo/
and bitcollider 0.6.0
(PD) 2004 The Bitzi Corporation
http://bitzi.com/
*/
#include "platform.h"
#include "extractor.h"
#include <math.h>
/**
* Read the specified number of bytes as a little-endian (least
* significant byte first) integer.
*/
static unsigned int
fread_le (const char *data)
{
int x;
unsigned int result = 0;
for (x = 0; x < 4; x++)
result |= ((unsigned char) data[x]) << (x * 8);
return result;
}
/* We implement our own rounding function, because the availability of
* C99's round(), nearbyint(), rint(), etc. seems to be spotty, whereas
* floor() is available in math.h on all C compilers.
*/
static double
round_double (double num)
{
return floor (num + 0.5);
}
#define ADD(s,t) do { if (0 != (ret = proc (proc_cls, "riff", t, EXTRACTOR_METAFORMAT_UTF8, "text/plain", s, strlen(s)+1))) goto FINISH; } while (0)
/* video/x-msvideo */
int
EXTRACTOR_riff_extract (const char *xdata,
size_t xsize,
EXTRACTOR_MetaDataProcessor proc,
void *proc_cls,
const char *options)
{
unsigned int blockLen;
unsigned int fps;
unsigned int duration;
size_t pos;
unsigned int width;
unsigned int height;
char codec[5];
char format[256];
int ret;
if (xsize < 32)
return 0;
if ((memcmp (&xdata[0],
"RIFF", 4) != 0) || (memcmp (&xdata[8], "AVI ", 4) != 0))
return 0;
if (memcmp (&xdata[12], "LIST", 4) != 0)
return 0;
if (memcmp (&xdata[20], "hdrlavih", 8) != 0)
return 0;
blockLen = fread_le (&xdata[28]);
/* begin of AVI header at 32 */
fps = (unsigned int) round_double ((double) 1.0e6 / fread_le (&xdata[32]));
duration = (unsigned int) round_double ((double) fread_le (&xdata[48])
* 1000 / fps);
width = fread_le (&xdata[64]);
height = fread_le (&xdata[68]);
/* pos: begin of video stream header */
pos = blockLen + 32;
if ((pos < blockLen) || (pos + 32 > xsize) || (pos > xsize))
return 0;
if (memcmp (&xdata[pos], "LIST", 4) != 0)
return 0;
blockLen = fread_le (&xdata[pos + 4]);
if (memcmp (&xdata[pos + 8], "strlstrh", 8) != 0)
return 0;
if (memcmp (&xdata[pos + 20], "vids", 4) != 0)
return 0;
ret = 0;
/* pos + 24: video stream header */
memcpy (codec, &xdata[pos + 24], 4);
codec[4] = '\0';
snprintf (format,
sizeof(format),
_("codec: %s, %u fps, %u ms"), codec, fps, duration);
ADD (format, EXTRACTOR_METATYPE_FORMAT);
snprintf (format,
sizeof(format),
"%ux%u", width, height);
ADD (format, EXTRACTOR_METATYPE_IMAGE_DIMENSIONS);
ADD ("video/x-msvideo", EXTRACTOR_METATYPE_MIMETYPE);
FINISH:
return ret;
}
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