Rescale the image pixels using the full precision.

[apitrace] / gui / apisurface.cpp

diff --git a/gui/apisurface.cpp b/gui/apisurface.cpp
index 3732ed5f717482ad976fbf6f9f0d9e447113b91c..22de5f0b0d873ab877c4c7dbd89fcdd7268e4fc6 100644 (file)
--- a/gui/apisurface.cpp
+++ b/gui/apisurface.cpp
@@ -33,90 +33,21 @@ struct ByteArrayBuf : public std::streambuf
 
 void ApiSurface::contentsFromBase64(const QByteArray &base64)
 {
-    QByteArray dataArray = QByteArray::fromBase64(base64);
-
-    image::Image *image;
+    m_base64Data = base64;
 
     /*
-     * Detect the PNG vs PFM images.
+     * We need to do the conversion to create the thumbnail
      */
-    const char pngSignature[] = {(char)0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A, 0};
-    if (dataArray.startsWith(pngSignature)) {
-        ByteArrayBuf buf(dataArray);
-        std::istream istr(&buf);
-        image = image::readPNG(istr);
-    } else {
-        image = image::readPNM(dataArray.data(), dataArray.size());
-    }
-
-    /*
-     * FIXME: Instead of converting to QImage here, we should be deferring the conversion
-     * to imageviewer.cpp.
-     *
-     * XXX: We still need the thumbnail though.
-     */
-
+    image::Image *image = imageFromBase64(base64);
     Q_ASSERT(image);
-
-    int width = image->width;
-    int height = image->height;
-
-    m_image = QImage(width, height, QImage::Format_ARGB32);
-
-    const unsigned char *srcRow = image->start();
-    for (int y = 0; y < height; ++y) {
-        QRgb *dst = (QRgb *)m_image.scanLine(y);
-
-        if (image->channelType == image::TYPE_UNORM8) {
-            const unsigned char *src = srcRow;
-            for (int x = 0; x < width; ++x) {
-                unsigned char rgba[4];
-                for (int c = 0; c < image->channels; ++c) {
-                    rgba[c] = *src++;
-                }
-                if (image->channels == 1) {
-                    // Use gray-scale instead of red
-                    rgba[1] = rgba[0];
-                    rgba[2] = rgba[0];
-                }
-                dst[x] = qRgba(rgba[0], rgba[1], rgba[2], rgba[3]);
-            }
-        } else {
-            const float *src = (const float *)srcRow;
-            for (int x = 0; x < width; ++x) {
-                unsigned char rgba[4] = {0, 0, 0, 0xff};
-                for (int c = 0; c < image->channels; ++c) {
-                    float f = *src++;
-                    unsigned char u;
-                    if (f >= 1.0f) {
-                        u = 255;
-                    } else if (f <= 0.0f) {
-                        u = 0;
-                    } else {
-                        u = f * 255 + 0.5;
-                    }
-                    rgba[c] = u;
-                }
-                if (image->channels == 1) {
-                    // Use gray-scale instead of red
-                    rgba[1] = rgba[0];
-                    rgba[2] = rgba[0];
-                }
-                dst[x] = qRgba(rgba[0], rgba[1], rgba[2], rgba[3]);
-            }
-        }
-
-        srcRow += image->stride();
-    }
-
+    QImage img = qimageFromRawImage(image);
+    m_thumb = thumbnail(img);
     delete image;
-
-    m_thumb = thumbnail(m_image);
 }
 
-QImage ApiSurface::image() const
+QByteArray ApiSurface::base64Data() const
 {
-    return m_image;
+    return m_base64Data;
 }
 
 QImage ApiSurface::thumb() const
@@ -175,3 +106,116 @@ void ApiFramebuffer::setType(const QString &str)
     m_type = str;
 }
 
+image::Image *
+ApiSurface::imageFromBase64(const QByteArray &base64)
+{
+    QByteArray dataArray = QByteArray::fromBase64(base64);
+    image::Image *image;
+
+    /*
+     * Detect the PNG vs PFM images.
+     */
+    const char pngSignature[] = {(char)0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A, 0};
+    if (dataArray.startsWith(pngSignature)) {
+        ByteArrayBuf buf(dataArray);
+        std::istream istr(&buf);
+        image = image::readPNG(istr);
+    } else {
+        image = image::readPNM(dataArray.data(), dataArray.size());
+    }
+
+    return image;
+}
+
+
+static inline unsigned char clamp(int x)
+{
+    if (x <= 0) {
+        return 0;
+    }
+    if (x > 255) {
+        return 255;
+    }
+    return (unsigned char) x;
+}
+
+static inline unsigned char clamp(float x)
+{
+    if (x <= 0.0f) {
+        return 0;
+    }
+    if (x > 255.0f) {
+        return 255;
+    }
+    return (unsigned char) (x + 0.5f);
+}
+
+
+QImage
+ApiSurface::qimageFromRawImage(const image::Image *image,
+                               float lowerValue,
+                               float upperValue,
+                               bool opaque,
+                               bool alpha)
+{
+    QImage img;
+    int width = image->width;
+    int height = image->height;
+
+    img = QImage(width, height, QImage::Format_ARGB32);
+
+    int offset = - lowerValue * 255;
+    int scale = 256 / (upperValue - lowerValue);
+
+    float offset_f = - lowerValue;
+    float scale_f = 255.0f / (upperValue - lowerValue);
+
+    int aMask = (opaque || alpha) ? 0xff : 0;
+
+    const unsigned char *srcRow = image->start();
+    for (int y = 0; y < height; ++y) {
+        QRgb *dst = (QRgb *)img.scanLine(y);
+
+        if (image->channelType == image::TYPE_UNORM8) {
+            const unsigned char *src = srcRow;
+            for (int x = 0; x < width; ++x) {
+                unsigned char rgba[4] = {0, 0, 0, 0xff};
+                for (int c = 0; c < image->channels; ++c) {
+                    rgba[c] = clamp(((*src++ + offset) * scale) >> 8);
+                }
+                if (image->channels == 1) {
+                    // Use gray-scale instead of red
+                    rgba[1] = rgba[0];
+                    rgba[2] = rgba[0];
+                }
+                if (alpha) {
+                    rgba[2] = rgba[1] = rgba[0] = rgba[3];
+                }
+                rgba[3] |= aMask;
+                dst[x] = qRgba(rgba[0], rgba[1], rgba[2], rgba[3]);
+            }
+        } else {
+            const float *src = (const float *)srcRow;
+            for (int x = 0; x < width; ++x) {
+                unsigned char rgba[4] = {0, 0, 0, 0xff};
+                for (int c = 0; c < image->channels; ++c) {
+                    rgba[c] = clamp((*src++ + offset_f)*scale_f);
+                }
+                if (image->channels == 1) {
+                    // Use gray-scale instead of red
+                    rgba[1] = rgba[0];
+                    rgba[2] = rgba[0];
+                }
+                if (alpha) {
+                    rgba[2] = rgba[1] = rgba[0] = rgba[3];
+                }
+                rgba[3] |= aMask;
+                dst[x] = qRgba(rgba[0], rgba[1], rgba[2], rgba[3]);
+            }
+        }
+
+        srcRow += image->stride();
+    }
+
+    return img;
+}