Add output for error metric

CLTool/src/clunix.cpp

@@ -84,8 +84,17 @@ int main(int argc, char **argv) {
 
   CompressedImage *ci = CompressImage(file, settings);
 
+  double PSNR = ComputePSNR(*ci, file);
+  if(PSNR > 0.0) {
+    fprintf(stdout, "PSNR: %.3f\n", PSNR);
+  }
+  else {
+    fprintf(stderr, "Error computing PSNR\n");
+  }
+
   // Cleanup 
   if(NULL != ci)
     delete ci;
+
   return 0;
 }

Core/include/CompressedImage.h

@@ -30,6 +30,8 @@ class CompressedImage {
 
   CompressedImage( const CompressedImage &other );
   ~CompressedImage();
+
+  bool DecompressImage(unsigned char *outBuf, unsigned int outBufSz) const;
 };
 
 #endif // _COMPRESSED_IMAGE_H_

Core/include/TexComp.h

@@ -25,4 +25,6 @@ typedef void (* CompressionFunc)(
   unsigned int height
 );
 
+extern double ComputePSNR(const CompressedImage &, const ImageFile &);
+
 #endif //_TEX_COMP_H_

Core/src/CompressedImage.cpp

@@ -2,12 +2,17 @@
 
 #include <string.h>
 #include <stdlib.h>
+#include <stdio.h>
+#include <assert.h>
+
+#include "BC7Compressor.h"
 
 CompressedImage::CompressedImage()
   : m_Width(0)
   , m_Height(0)
   , m_Format(ECompressionFormat(-1))
   , m_Data(0)
+  , m_DataSz(0)
 { }
 
 CompressedImage::CompressedImage( const CompressedImage &other )
@@ -15,6 +20,7 @@ CompressedImage::CompressedImage( const CompressedImage &other )
   , m_Height(other.m_Height)
   , m_Format(other.m_Format)
   , m_Data(0)
+  , m_DataSz(0)
 {
   InitData(other.m_Data);
 }
@@ -29,23 +35,24 @@ CompressedImage::CompressedImage(
 , m_Height(height)
 , m_Format(format)
 , m_Data(0)
+, m_DataSz(0)
 {
   InitData(data);
 }
 
 void CompressedImage::InitData(const unsigned char *withData) {
-  unsigned int dataSz = 0;
+  m_DataSz = 0;
   int uncompDataSz = m_Width * m_Height * 4;
 
   switch(m_Format) {
-    case eCompressionFormat_DXT1: dataSz = uncompDataSz / 8; break;
-    case eCompressionFormat_DXT5: dataSz = uncompDataSz / 4; break;
-    case eCompressionFormat_BPTC: dataSz = uncompDataSz / 4; break;
+    case eCompressionFormat_DXT1: m_DataSz = uncompDataSz / 8; break;
+    case eCompressionFormat_DXT5: m_DataSz = uncompDataSz / 4; break;
+    case eCompressionFormat_BPTC: m_DataSz = uncompDataSz / 4; break;
   }
   
-  if(dataSz > 0) {
-    m_Data = new unsigned char[dataSz];
-    memcpy(m_Data, withData, dataSz);
+  if(m_DataSz > 0) {
+    m_Data = new unsigned char[m_DataSz];
+    memcpy(m_Data, withData, m_DataSz);
   }
 }
 
@@ -55,3 +62,34 @@ CompressedImage::~CompressedImage() {
     m_Data = NULL;
   }
 }
+
+bool CompressedImage::DecompressImage(unsigned char *outBuf, unsigned int outBufSz) const {
+
+  // First make sure that we have enough data
+  int dataSz = 0;
+  switch(m_Format) {
+    case eCompressionFormat_DXT1: dataSz = m_DataSz * 8; break;
+    case eCompressionFormat_DXT5: dataSz = m_DataSz * 4; break;
+    case eCompressionFormat_BPTC: dataSz = m_DataSz * 4; break;
+  }
+
+  if(dataSz > outBufSz) {
+    fprintf(stderr, "Not enough space to store entire decompressed image! "
+                    "Got %d bytes, but need %d!\n", outBufSz, dataSz);
+    return false;
+  }
+
+  switch(m_Format) {
+  case eCompressionFormat_BPTC: 
+    BC7C::DecompressImageBC7(m_Data, outBuf, m_Width, m_Height);
+    break;
+
+  default:
+    const char *errStr = "Have not implemented decompression method.";
+    fprintf(stderr, "%s\n", errStr);
+    assert(!errStr);
+    return false;
+  }
+
+  return true;
+}

Core/src/TexComp.cpp

@@ -2,6 +2,7 @@
 #include "TexComp.h"
 #include "ThreadGroup.h"
 
+#include <math.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <assert.h>
@@ -148,4 +149,57 @@ CompressedImage * CompressImage(
   delete [] cmpData;
 
   return outImg;
-} 
+}
+
+template <typename T>
+static inline T sad(const T &a, const T &b) {
+  return (a > b)? a - b : b - a;
+}
+
+double ComputePSNR(const CompressedImage &ci, const ImageFile &file) {
+  unsigned int imageSz = 4 * file.GetWidth() * file.GetHeight();
+  unsigned char *unCompData = new unsigned char[imageSz];
+  if(!(ci.DecompressImage(unCompData, imageSz))) {
+    ReportError("Failed to decompress image.");
+    return -1.0f;
+  }
+
+  const unsigned char *rawData = file.GetPixels();
+
+  const double wr = 1.0;
+  const double wg = 1.0;
+  const double wb = 1.0;
+    
+  double MSE = 0.0;
+  for(int i = 0; i < imageSz; i+=4) {
+
+    const unsigned char *pixelDataRaw = rawData + i;
+    const unsigned char *pixelDataUncomp = unCompData + i;
+
+    double dr = double(sad(pixelDataRaw[0], pixelDataUncomp[0])) * wr;
+    double dg = double(sad(pixelDataRaw[1], pixelDataUncomp[1])) * wg;
+    double db = double(sad(pixelDataRaw[2], pixelDataUncomp[2])) * wb;
+
+    const double pixelMSE = 
+      (double(dr) * double(dr)) + 
+      (double(dg) * double(dg)) + 
+      (double(db) * double(db));
+
+    //fprintf(stderr, "Pixel MSE: %f\n", pixelMSE);
+    MSE += pixelMSE;
+  }
+
+  MSE /= (double(file.GetWidth()) * double(file.GetHeight()));
+
+  double MAXI = 
+    (255.0 * wr) * (255.0 * wr) + 
+    (255.0 * wg) * (255.0 * wg) + 
+    (255.0 * wb) * (255.0 * wb);
+
+  double PSNR = 10 * log10(MAXI/MSE);
+
+  // Cleanup
+  delete unCompData;
+  return PSNR;
+
+}

IO/src/ImageFile.cpp

@@ -196,6 +196,11 @@ bool ImageFile::LoadImage(const unsigned char *rawImageData) {
   const unsigned int aw = ((m_Width + 3) >> 2) << 2;
   const unsigned int ah = ((m_Height + 3) >> 2) << 2;
 
+#ifndef NDEBUG
+  if(aw != m_Width || ah != m_Height)
+    fprintf(stderr, "Warning: Image dimension not multiple of four. Space will be filled with black.\n");
+#endif
+
   int byteIdx = 0;
   for(int i = 0; i < ah; i+=4) {
     for(int j = 0; j < aw; j+= 4) {

IO/src/ImageLoaderPNG.cpp

@@ -112,7 +112,7 @@ bool ImageLoaderPNG::ReadData() {
 	
 	unsigned int byteIdx = 0;
 	for(int j = 0; j < m_Width; j++) {
-
+ 	  m_RedData[rowOffset + j] = rowData[byteIdx++];
 	}
 
 	assert(byteIdx == bpr);