ImageDecoder* ImageDecoder::create(const SharedBuffer& data, ImageSource::AlphaOption alphaOption, ImageSource::GammaAndColorProfileOption gammaAndColorProfileOption)
{
static const unsigned lengthOfLongestSignature = 14; // To wit: "RIFF????WEBPVP"
char contents[lengthOfLongestSignature];
unsigned length = copyFromSharedBuffer(contents, lengthOfLongestSignature, data, 0);
if (length < lengthOfLongestSignature)
return 0;
if (matchesGIFSignature(contents))
return new GIFImageDecoder(alphaOption, gammaAndColorProfileOption);
if (matchesPNGSignature(contents))
return new PNGImageDecoder(alphaOption, gammaAndColorProfileOption);
if (matchesJPEGSignature(contents))
return new JPEGImageDecoder(alphaOption, gammaAndColorProfileOption);
#if USE(WEBP)
if (matchesWebPSignature(contents))
return new WEBPImageDecoder(alphaOption, gammaAndColorProfileOption);
#endif
if (matchesBMPSignature(contents))
return new BMPImageDecoder(alphaOption, gammaAndColorProfileOption);
if (matchesICOSignature(contents) || matchesCURSignature(contents))
return new ICOImageDecoder(alphaOption, gammaAndColorProfileOption);
return 0;
}
PassOwnPtr<ImageDecoder> ImageDecoder::create(const SharedBuffer& data, ImageSource::AlphaOption alphaOption, ImageSource::GammaAndColorProfileOption gammaAndColorProfileOption)
{
static const unsigned longestSignatureLength = sizeof("RIFF????WEBPVP") - 1;
ASSERT(longestSignatureLength == 14);
size_t maxDecodedBytes = Platform::current()->maxDecodedImageBytes();
char contents[longestSignatureLength];
if (copyFromSharedBuffer(contents, longestSignatureLength, data, 0) < longestSignatureLength)
return nullptr;
if (matchesJPEGSignature(contents))
return adoptPtr(new JPEGImageDecoder(alphaOption, gammaAndColorProfileOption, maxDecodedBytes));
if (matchesPNGSignature(contents))
return adoptPtr(new PNGImageDecoder(alphaOption, gammaAndColorProfileOption, maxDecodedBytes));
if (matchesGIFSignature(contents))
return adoptPtr(new GIFImageDecoder(alphaOption, gammaAndColorProfileOption, maxDecodedBytes));
if (matchesICOSignature(contents) || matchesCURSignature(contents))
return adoptPtr(new ICOImageDecoder(alphaOption, gammaAndColorProfileOption, maxDecodedBytes));
if (matchesWebPSignature(contents))
return adoptPtr(new WEBPImageDecoder(alphaOption, gammaAndColorProfileOption, maxDecodedBytes));
if (matchesBMPSignature(contents))
return adoptPtr(new BMPImageDecoder(alphaOption, gammaAndColorProfileOption, maxDecodedBytes));
return nullptr;
}
ImageDecoder* ImageDecoder::create(const SharedBuffer& data)
{
// We need at least 4 bytes to figure out what kind of image we're dealing
// with.
static const unsigned maxMarkerLength = 4;
char contents[maxMarkerLength];
unsigned length = copyFromSharedBuffer(contents, maxMarkerLength, data, 0);
if (length < maxMarkerLength)
return 0;
// GIFs begin with GIF8(7 or 9).
if (strncmp(contents, "GIF8", 4) == 0)
return new GIFImageDecoder();
// Test for PNG.
if (!memcmp(contents, "\x89\x50\x4E\x47", 4))
return new PNGImageDecoder();
// JPEG
if (!memcmp(contents, "\xFF\xD8\xFF", 3))
return new JPEGImageDecoder();
// BMP
if (strncmp(contents, "BM", 2) == 0)
return new BMPImageDecoder();
// ICOs always begin with a 2-byte 0 followed by a 2-byte 1.
// CURs begin with 2-byte 0 followed by 2-byte 2.
if (!memcmp(contents, "\x00\x00\x01\x00", 4) || !memcmp(contents, "\x00\x00\x02\x00", 4))
return new ICOImageDecoder();
// Give up. We don't know what the heck this is.
return 0;
}