Remove unused legacy code from the jpeg image plugin

A long time ago, in a Qt version far, far, away there was a
parameter string mechanism for asking for header details,
requesting scaling, and so on.  This has since been replaced
with actual real API's and it is no longer possible to pass
such parameter strings to the image plugins.  This change
removes the crufty beloved old code.

Reviewed-by: Sarah Smith

2 files changed, 11 insertions, 134 deletions

diff --git a/src/plugins/imageformats/jpeg/qjpeghandler.cpp b/src/plugins/imageformats/jpeg/qjpeghandler.cpp
index 54bbcda..aa239ec 100644
--- a/src/plugins/imageformats/jpeg/qjpeghandler.cpp
+++ b/src/plugins/imageformats/jpeg/qjpeghandler.cpp
@@ -84,7 +84,7 @@ class QImageSmoothScaler
 public:
     QImageSmoothScaler(const int w, const int h, const QImage &src);
     QImageSmoothScaler(const int srcWidth, const int srcHeight,
-                       const char *parameters);
+                       const int dstWidth, const int dstHeight);
 
     virtual ~QImageSmoothScaler(void);
 
@@ -123,33 +123,9 @@ QImageSmoothScaler::QImageSmoothScaler(const int w, const int h,
 }
 
 QImageSmoothScaler::QImageSmoothScaler(const int srcWidth, const int srcHeight,
-                                       const char *parameters)
+                                       const int dstWidth, const int dstHeight)
 {
-    char    sModeStr[1024];
-    int	    t1;
-    int	    t2;
-    int	    dstWidth;
-    int	    dstHeight;
-
-    sModeStr[0] = '\0';
-
     d = new QImageSmoothScalerPrivate;
-#if defined(Q_OS_WIN) && !defined(Q_OS_WINCE) && defined(_MSC_VER) && _MSC_VER >= 1400
-    sscanf_s(parameters, "Scale( %i, %i, %1023s )", &dstWidth, &dstHeight, sModeStr, sizeof(sModeStr));
-#else
-    sscanf(parameters, "Scale( %i, %i, %s )", &dstWidth, &dstHeight, sModeStr);
-#endif
-    QString sModeQStr = QString::fromLatin1(sModeStr);
-
-    t1 = srcWidth * dstHeight;
-    t2 = srcHeight * dstWidth;
-
-    if (((sModeQStr == QLatin1String("ScaleMin")) && (t1 > t2)) || ((sModeQStr == QLatin1String("ScaleMax")) && (t2 < t2))) {
-	dstHeight = t2 / srcWidth;
-    } else if (sModeQStr != QLatin1String("ScaleFree")) {
-	dstWidth = t1 / srcHeight;
-    }
-
     d->setup(srcWidth, srcHeight, dstWidth, dstHeight, 0);
 }
 
@@ -467,8 +443,8 @@ QImage QImageSmoothScaler::scale()
 class jpegSmoothScaler : public QImageSmoothScaler
 {
 public:
-    jpegSmoothScaler(struct jpeg_decompress_struct *info, const char *params):
-	QImageSmoothScaler(info->output_width, info->output_height, params)
+    jpegSmoothScaler(struct jpeg_decompress_struct *info, int dstWidth, int dstHeight)
+	: QImageSmoothScaler(info->output_width, info->output_height, dstWidth, dstHeight)
     {
 	cinfo = info;
 	cols24Bit = scaledWidth() * 3;
@@ -637,18 +613,6 @@ inline my_jpeg_source_mgr::my_jpeg_source_mgr(QIODevice *device)
 }
 
 
-static void scaleSize(int &reqW, int &reqH, int imgW, int imgH, Qt::AspectRatioMode mode)
-{
-    if (mode == Qt::IgnoreAspectRatio)
-        return;
-    int t1 = imgW * reqH;
-    int t2 = reqW * imgH;
-    if ((mode == Qt::KeepAspectRatio && (t1 > t2)) || (mode == Qt::KeepAspectRatioByExpanding && (t1 < t2)))
-        reqH = t2 / imgW;
-    else
-        reqW = t1 / imgH;
-}
-
 static bool read_jpeg_size(QIODevice *device, int &w, int &h)
 {
     bool rt = false;
@@ -763,8 +727,7 @@ static bool ensureValidImage(QImage *dest, struct jpeg_decompress_struct *info,
 }
 
 static bool read_jpeg_image(QIODevice *device, QImage *outImage,
-                            const QByteArray &parameters, QSize scaledSize,
-                            int inQuality )
+                            QSize scaledSize, int inQuality )
 {
 #ifdef QT_NO_IMAGE_SMOOTHSCALE
     Q_UNUSED( scaledSize );
@@ -794,16 +757,9 @@ static bool read_jpeg_image(QIODevice *device, QImage *outImage,
         if (quality < 0)
             quality = 75;
 
-        QString params = QString::fromLatin1(parameters);
-        params.simplified();
-        int sWidth = 0, sHeight = 0;
-        char sModeStr[1024] = "";
-        Qt::AspectRatioMode sMode;
-
 #ifndef QT_NO_IMAGE_SMOOTHSCALE
         // If high quality not required, shrink image during decompression
-        if (scaledSize.isValid() && !scaledSize.isEmpty() && quality < HIGH_QUALITY_THRESHOLD
-            && !params.contains(QLatin1String("GetHeaderInformation")) ) {
+        if (scaledSize.isValid() && !scaledSize.isEmpty() && quality < HIGH_QUALITY_THRESHOLD) {
             cinfo.scale_denom = qMin(cinfo.image_width / scaledSize.width(),
                                      cinfo.image_width / scaledSize.height());
             if (cinfo.scale_denom < 2) {
@@ -829,93 +785,15 @@ static bool read_jpeg_image(QIODevice *device, QImage *outImage,
 
         (void) jpeg_start_decompress(&cinfo);
 
-        if (params.contains(QLatin1String("GetHeaderInformation"))) {
-            if (!ensureValidImage(outImage, &cinfo, true))
-                longjmp(jerr.setjmp_buffer, 1);
-        } else if (params.contains(QLatin1String("Scale"))) {
-#if defined(_MSC_VER) && _MSC_VER >= 1400 && !defined(Q_OS_WINCE)
-            sscanf_s(params.toLatin1().data(), "Scale(%i, %i, %1023s)",
-                     &sWidth, &sHeight, sModeStr, sizeof(sModeStr));
-#else
-            sscanf(params.toLatin1().data(), "Scale(%i, %i, %1023s)",
-                   &sWidth, &sHeight, sModeStr);
-#endif
-
-            QString sModeQStr(QString::fromLatin1(sModeStr));
-            if (sModeQStr == QLatin1String("IgnoreAspectRatio")) {
-                sMode = Qt::IgnoreAspectRatio;
-            } else if (sModeQStr == QLatin1String("KeepAspectRatio")) {
-                sMode = Qt::KeepAspectRatio;
-            } else if (sModeQStr == QLatin1String("KeepAspectRatioByExpanding")) {
-                sMode = Qt::KeepAspectRatioByExpanding;
-            } else {
-                qDebug("read_jpeg_image: invalid aspect ratio mode \"%s\", see QImage::AspectRatioMode documentation", sModeStr);
-                sMode = Qt::KeepAspectRatio;
-            }
-
-//            qDebug("Parameters ask to scale the image to %i x %i AspectRatioMode: %s", sWidth, sHeight, sModeStr);
-            scaleSize(sWidth, sHeight, cinfo.output_width, cinfo.output_height, sMode);
-//            qDebug("Scaling the jpeg to %i x %i", sWidth, sHeight, sModeStr);
-
-            if (cinfo.output_components == 3 || cinfo.output_components == 4) {
-                if (outImage->size() != QSize(sWidth, sHeight) || outImage->format() != QImage::Format_RGB32)
-                    *outImage = QImage(sWidth, sHeight, QImage::Format_RGB32);
-            } else if (cinfo.output_components == 1) {
-                if (outImage->size() != QSize(sWidth, sHeight) || outImage->format() != QImage::Format_Indexed8)
-                    *outImage = QImage(sWidth, sHeight, QImage::Format_Indexed8);
-                outImage->setColorCount(256);
-                for (int i = 0; i < 256; ++i)
-                    outImage->setColor(i, qRgb(i,i,i));
-            } else {
-                // Unsupported format
-            }
-            if (outImage->isNull())
-                longjmp(jerr.setjmp_buffer, 1);
-
-            if (!outImage->isNull()) {
-                QImage tmpImage(cinfo.output_width, 1, QImage::Format_RGB32);
-                uchar* inData = tmpImage.bits();
-                uchar* outData = outImage->bits();
-                int out_bpl = outImage->bytesPerLine();
-                while (cinfo.output_scanline < cinfo.output_height) {
-                    int outputLine = sHeight * cinfo.output_scanline / cinfo.output_height;
-                    (void) jpeg_read_scanlines(&cinfo, &inData, 1);
-                    if (cinfo.output_components == 3) {
-                        uchar *in = inData;
-                        QRgb *out = (QRgb*)outData + outputLine * out_bpl;
-                        for (uint i=0; i<cinfo.output_width; i++) {
-// ### Only scaling down an image works, I don't think scaling up will work at the moment
-// ### An idea I have to make this a smooth scale is to progressively add the pixel values up
-// When scaling down, multiple values are being over drawn in to the output buffer.
-// Instead, a weighting based on the distance the line or pixel is from the output pixel determines
-// the weight of it when added to the output buffer. At present it is a non-smooth scale which is
-// inefficently implemented, it still uncompresses all the jpeg, an optimization for progressive
-// jpegs could be made if scaling by say 50% or some other special cases
-                            out[sWidth * i / cinfo.output_width] = qRgb(in[0], in[1], in[2]);
-                            in += 3;
-                        }
-                    } else {
-// ### Need to test the case where the jpeg is grayscale, need some black and white jpegs to test
-// this code. (also only scales down and probably won't scale to a larger size)
-                        uchar *in = inData;
-                        uchar *out = outData + outputLine*out_bpl;
-                        for (uint i=0; i<cinfo.output_width; i++) {
-                            out[sWidth * i / cinfo.output_width] = in[i];
-                        }
-                    }
-                }
-                (void) jpeg_finish_decompress(&cinfo);
-            }
 #ifndef QT_NO_IMAGE_SMOOTHSCALE
-        } else if (scaledSize.isValid() && scaledSize != QSize(cinfo.output_width, cinfo.output_height)
+        if (scaledSize.isValid() && scaledSize != QSize(cinfo.output_width, cinfo.output_height)
             && quality >= HIGH_QUALITY_THRESHOLD) {
 
-            jpegSmoothScaler scaler(&cinfo, QString().sprintf("Scale( %d, %d, ScaleFree )",
-                                                              scaledSize.width(),
-                                                              scaledSize.height()).toLatin1().data());
+            jpegSmoothScaler scaler(&cinfo, scaledSize.width(), scaledSize.height());
             *outImage = scaler.scale();
+        } else
 #endif
-        } else {
+        {
             if (!ensureValidImage(outImage, &cinfo))
                 longjmp(jerr.setjmp_buffer, 1);
 
@@ -1224,7 +1102,7 @@ bool QJpegHandler::read(QImage *image)
 {
     if (!canRead())
         return false;
-    return read_jpeg_image(device(), image, parameters, scaledSize, quality);
+    return read_jpeg_image(device(), image, scaledSize, quality);
 }
 
 bool QJpegHandler::write(const QImage &image)
diff --git a/src/plugins/imageformats/jpeg/qjpeghandler.h b/src/plugins/imageformats/jpeg/qjpeghandler.h
index 654c078..0a14a88 100644
--- a/src/plugins/imageformats/jpeg/qjpeghandler.h
+++ b/src/plugins/imageformats/jpeg/qjpeghandler.h
@@ -66,7 +66,6 @@ public:
 
 private:
     int quality;
-    QByteArray parameters;
     QSize scaledSize;
 };