From e4e0862c2ebe205f8c50897f15bfe256089d6ac9 Mon Sep 17 00:00:00 2001
From: "andrey.morozov" <andrey.morozov@itseez.com>
Date: Sat, 29 Jun 2013 22:00:26 +0400
Subject: [PATCH] added support image with alpha channel
---
modules/highgui/src/grfmt_webp.cpp | 115 +++++++++++++++++++---------
modules/highgui/src/grfmt_webp.hpp | 7 +-
modules/highgui/test/test_grfmt.cpp | 10 ++-
3 files changed, 94 insertions(+), 38 deletions(-)
diff --git a/modules/highgui/src/grfmt_webp.cpp b/modules/highgui/src/grfmt_webp.cpp
index 270262095..fd9682a79 100644
--- a/modules/highgui/src/grfmt_webp.cpp
+++ b/modules/highgui/src/grfmt_webp.cpp
@@ -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)
diff --git a/modules/highgui/src/grfmt_webp.hpp b/modules/highgui/src/grfmt_webp.hpp
index f37e6e9f4..ea692bf8d 100644
--- a/modules/highgui/src/grfmt_webp.hpp
+++ b/modules/highgui/src/grfmt_webp.hpp
@@ -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
diff --git a/modules/highgui/test/test_grfmt.cpp b/modules/highgui/test/test_grfmt.cpp
index d4e18dd2d..28af633da 100644
--- a/modules/highgui/test/test_grfmt.cpp
+++ b/modules/highgui/test/test_grfmt.cpp
@@ -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