added support image with alpha channel

This commit is contained in:
andrey.morozov 2013-06-29 22:00:26 +04:00
parent 8d0452ed59
commit e4e0862c2e
3 changed files with 94 additions and 38 deletions

View File

@ -46,6 +46,7 @@
#include <webp/decode.h>
#include <webp/encode.h>
#include <stdio.h>
#include <limits.h>
@ -53,17 +54,38 @@
#include "opencv2/imgproc.hpp"
const size_t WEBP_HEADER_SIZE = 32;
namespace cv
{
WebPDecoder::WebPDecoder()
{
m_signature = "RIFF....WEBPVP8 ";
m_buf_supported = true;
}
WebPDecoder::~WebPDecoder()
WebPDecoder::~WebPDecoder() {}
size_t WebPDecoder::signatureLength() const
{
return WEBP_HEADER_SIZE;
}
bool WebPDecoder::checkSignature(const String & signature) const
{
bool ret = false;
if(signature.size() >= WEBP_HEADER_SIZE)
{
WebPBitstreamFeatures features;
if(VP8_STATUS_OK == WebPGetFeatures((uint8_t *)signature.c_str(),
WEBP_HEADER_SIZE, &features))
{
ret = true;
}
}
return ret;
}
ImageDecoder WebPDecoder::newDecoder() const
@ -71,20 +93,6 @@ ImageDecoder WebPDecoder::newDecoder() const
return new WebPDecoder;
}
bool WebPDecoder::checkSignature( const String& signature ) const
{
size_t len = signatureLength();
bool ret = false;
if(signature.size() >= len)
{
ret = ( (memcmp(signature.c_str(), m_signature.c_str(), 4) == 0) &&
(memcmp(signature.c_str() + 8, m_signature.c_str() + 8, 4) == 0) );
}
return ret;
}
bool WebPDecoder::readHeader()
{
if (m_buf.empty())
@ -99,16 +107,16 @@ bool WebPDecoder::readHeader()
}
fseek(wfile, 0, SEEK_END);
size_t wfile_size = ftell(wfile);
long int wfile_size = ftell(wfile);
fseek(wfile, 0, SEEK_SET);
if(wfile_size > (size_t)INT_MAX)
if(wfile_size > static_cast<long int>(INT_MAX))
{
fclose(wfile);
return false;
}
data.create(1, (int)wfile_size, CV_8U);
data.create(1, wfile_size, CV_8U);
size_t data_size = fread(data.data, 1, wfile_size, wfile);
@ -117,7 +125,7 @@ bool WebPDecoder::readHeader()
fclose(wfile);
}
if( data_size < wfile_size )
if(static_cast<long int>(data_size) != wfile_size)
{
return false;
}
@ -127,9 +135,23 @@ bool WebPDecoder::readHeader()
data = m_buf;
}
if(WebPGetInfo(data.data, data.total(), &m_width, &m_height) == 1)
WebPBitstreamFeatures features;
if(VP8_STATUS_OK == WebPGetFeatures(data.data, WEBP_HEADER_SIZE, &features))
{
m_type = CV_8UC3;
m_width = features.width;
m_height = features.height;
if (features.has_alpha)
{
m_type = CV_8UC4;
channels = 4;
}
else
{
m_type = CV_8UC3;
channels = 3;
}
return true;
}
@ -140,17 +162,24 @@ bool WebPDecoder::readData(Mat &img)
{
if( m_width > 0 && m_height > 0 )
{
if (img.cols != m_width || img.rows != m_height || img.type() != m_type)
{
img.create(m_height, m_width, m_type);
}
uchar* out_data = img.data;
unsigned int out_data_size = m_width * m_height * 3 * sizeof(uchar);
size_t out_data_size = img.cols * img.rows * img.elemSize();
uchar *res_ptr = 0;
if (channels == 3)
{
res_ptr = WebPDecodeBGRInto(data.data, data.total(), out_data, out_data_size, img.step);
res_ptr = WebPDecodeBGRInto(data.data, data.total(), out_data,
out_data_size, img.step);
}
else if (channels == 4)
{
res_ptr = WebPDecodeBGRAInto(data.data, data.total(), out_data, out_data_size, img.step);
res_ptr = WebPDecodeBGRAInto(data.data, data.total(), out_data,
out_data_size, img.step);
}
if(res_ptr == out_data)
@ -168,9 +197,7 @@ WebPEncoder::WebPEncoder()
m_buf_supported = true;
}
WebPEncoder::~WebPEncoder()
{
}
WebPEncoder::~WebPEncoder() { }
ImageEncoder WebPEncoder::newEncoder() const
{
@ -187,19 +214,19 @@ bool WebPEncoder::write(const Mat& img, const std::vector<int>& params)
size_t size = 0;
bool comp_lossless = true;
int quality = 100;
float quality = 100.0f;
if (params.size() > 1)
{
if (params[0] == CV_IMWRITE_WEBP_QUALITY)
{
comp_lossless = false;
quality = params[1];
if (quality < 1)
quality = static_cast<float>(params[1]);
if (quality < 1.0f)
{
quality = 1;
quality = 1.0f;
}
if (quality > 100)
if (quality > 100.0f)
{
comp_lossless = true;
}
@ -219,14 +246,32 @@ bool WebPEncoder::write(const Mat& img, const std::vector<int>& params)
image = &temp;
channels = 3;
}
else if (channels == 2)
{
return false;
}
if (comp_lossless)
{
size = WebPEncodeLosslessBGR(image->data, width, height, ((width * 3 + 3) & ~3), &out);
if(channels == 3)
{
size = WebPEncodeLosslessBGR(image->data, width, height, image->step, &out);
}
else if(channels == 4)
{
size = WebPEncodeLosslessBGRA(image->data, width, height, image->step, &out);
}
}
else
{
size = WebPEncodeBGR(image->data, width, height, ((width * 3 + 3) & ~3), (float)quality, &out);
if(channels == 3)
{
size = WebPEncodeBGR(image->data, width, height, image->step, quality, &out);
}
else if(channels == 4)
{
size = WebPEncodeBGRA(image->data, width, height, image->step, quality, &out);
}
}
if(size > 0)

View File

@ -47,6 +47,8 @@
#ifdef HAVE_WEBP
namespace cv
{
@ -60,12 +62,15 @@ public:
bool readData( Mat& img );
bool readHeader();
void close();
bool checkSignature( const String& signature ) const;
size_t signatureLength() const;
bool checkSignature( const String& signature) const;
ImageDecoder newDecoder() const;
protected:
Mat data;
int channels;
};
class WebPEncoder : public BaseImageEncoder

View File

@ -387,7 +387,7 @@ TEST(Highgui_WebP, encode_decode_lossless_webp)
TEST(Highgui_WebP, encode_decode_lossy_webp)
{
cvtest::TS& ts = *cvtest::TS::ptr();
std::string input = std::string(ts.get_data_path()) + "/../cv/shared/lena.png";
std::string input = std::string(ts.get_data_path()) + "../cv/shared/lena.png";
cv::Mat img = cv::imread(input);
ASSERT_FALSE(img.empty());
@ -402,13 +402,16 @@ TEST(Highgui_WebP, encode_decode_lossy_webp)
cv::Mat img_webp = cv::imread(output);
remove(output.c_str());
EXPECT_FALSE(img_webp.empty());
EXPECT_EQ(3, img_webp.channels());
EXPECT_EQ(512, img_webp.cols);
EXPECT_EQ(512, img_webp.rows);
}
}
TEST(Highgui_WebP, encode_decode_with_alpha_webp)
{
cvtest::TS& ts = *cvtest::TS::ptr();
std::string input = std::string(ts.get_data_path()) + "/../cv/shared/lena.png";
std::string input = std::string(ts.get_data_path()) + "../cv/shared/lena.png";
cv::Mat img = cv::imread(input);
ASSERT_FALSE(img.empty());
@ -424,6 +427,9 @@ TEST(Highgui_WebP, encode_decode_with_alpha_webp)
cv::Mat img_webp = cv::imread(output);
remove(output.c_str());
EXPECT_FALSE(img_webp.empty());
EXPECT_EQ(4, img_webp.channels());
EXPECT_EQ(512, img_webp.cols);
EXPECT_EQ(512, img_webp.rows);
}
#endif