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Diffstat (limited to 'bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/internal/image/JPEGFrameHeader.java')
-rwxr-xr-xbundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/internal/image/JPEGFrameHeader.java203
1 files changed, 203 insertions, 0 deletions
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/internal/image/JPEGFrameHeader.java b/bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/internal/image/JPEGFrameHeader.java
new file mode 100755
index 0000000000..be2cf6c6d3
--- /dev/null
+++ b/bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/internal/image/JPEGFrameHeader.java
@@ -0,0 +1,203 @@
+package org.eclipse.swt.internal.image;
+
+/*
+ * Licensed Materials - Property of IBM,
+ * (c) Copyright IBM Corp 2000
+ */
+
+import org.eclipse.swt.*;
+
+final class JPEGFrameHeader extends JPEGVariableSizeSegment {
+ int maxVFactor;
+ int maxHFactor;
+ public int[][] componentParameters;
+
+ public JPEGFrameHeader(byte[] reference) {
+ super(reference);
+ }
+
+ public JPEGFrameHeader(LEDataInputStream byteStream) {
+ super(byteStream);
+ initializeComponentParameters();
+ }
+
+ public int getSamplePrecision() {
+ return reference[4] & 0xFF;
+ }
+
+ public int getNumberOfLines() {
+ return (reference[5] & 0xFF) << 8 | (reference[6] & 0xFF);
+ }
+
+ public int getSamplesPerLine() {
+ return (reference[7] & 0xFF) << 8 | (reference[8] & 0xFF);
+ }
+
+ public int getNumberOfImageComponents() {
+ return reference[9] & 0xFF;
+ }
+
+ public void setSamplePrecision(int precision) {
+ reference[4] = (byte)(precision & 0xFF);
+ }
+
+ public void setNumberOfLines(int anInteger) {
+ reference[5] = (byte)((anInteger & 0xFF00) >> 8);
+ reference[6] = (byte)(anInteger & 0xFF);
+ }
+
+ public void setSamplesPerLine(int samples) {
+ reference[7] = (byte)((samples & 0xFF00) >> 8);
+ reference[8] = (byte)(samples & 0xFF);
+ }
+
+ public void setNumberOfImageComponents(int anInteger) {
+ reference[9] = (byte)(anInteger & 0xFF);
+ }
+
+ public int getMaxHFactor() {
+ return maxHFactor;
+ }
+
+ public int getMaxVFactor() {
+ return maxVFactor;
+ }
+
+ public void setMaxHFactor(int anInteger) {
+ maxHFactor = anInteger;
+ }
+
+ public void setMaxVFactor(int anInteger) {
+ maxVFactor = anInteger;
+ }
+
+ void initializeComponentParameters() {
+ int nf = getNumberOfImageComponents();
+ int[][] compSpecParams = new int[0][];
+ int hmax = 1;
+ int vmax = 1;
+ for (int i = 0; i < nf; i++) {
+ int ofs = i * 3 + 10;
+ int ci = reference[ofs] & 0xFF;
+ int hi = (reference[ofs + 1] & 0xFF) / 16;
+ int vi = (reference[ofs + 1] & 0xFF) % 16;
+ int tqi = reference[ofs + 2] & 0xFF;
+ if (hi > hmax) {
+ hmax = hi;
+ }
+ if (vi > vmax) {
+ vmax = vi;
+ }
+ int[] compParam = new int[5];
+ compParam[0] = tqi;
+ compParam[1] = hi;
+ compParam[2] = vi;
+ if (compSpecParams.length < ci) {
+ int[][] newParams = new int[ci][];
+ System.arraycopy(compSpecParams, 0, newParams, 0, compSpecParams.length);
+ compSpecParams = newParams;
+ }
+ compSpecParams[ci - 1] = compParam;
+ }
+ int x = getSamplesPerLine();
+ int y = getNumberOfLines();
+ int[] multiples = new int[] { 8, 16, 24, 32 };
+ for (int i = 0; i < compSpecParams.length; i++) {
+ int[] compParam = compSpecParams[i];
+ int hi = compParam[1];
+ int vi = compParam[2];
+ int compWidth = (x * hi + hmax - 1) / hmax;
+ int compHeight = (y * vi + vmax - 1) / vmax;
+ int dsWidth = roundUpToMultiple(compWidth, multiples[hi - 1]);
+ int dsHeight = roundUpToMultiple(compHeight, multiples[vi - 1]);
+ compParam[3] = dsWidth;
+ compParam[4] = dsHeight;
+ }
+ setMaxHFactor(hmax);
+ setMaxVFactor(vmax);
+ componentParameters = compSpecParams;
+ }
+
+ public void initializeContents() {
+ int nf = getNumberOfImageComponents();
+ if (nf == 0 || nf != componentParameters.length) {
+ SWT.error(SWT.ERROR_INVALID_IMAGE);
+ }
+ int hmax = 0;
+ int vmax = 0;
+ int[][] compSpecParams = componentParameters;
+ for (int i = 0; i < nf; i++) {
+ int ofs = i * 3 + 10;
+ int[] compParam = compSpecParams[i];
+ int hi = compParam[1];
+ int vi = compParam[2];
+ if (hi * vi > 4) {
+ SWT.error(SWT.ERROR_INVALID_IMAGE);
+ }
+ reference[ofs] = (byte)(i + 1);
+ reference[ofs + 1] = (byte)(hi * 16 + vi);
+ reference[ofs + 2] = (byte)(compParam[0]);
+ if (hi > hmax) hmax = hi;
+ if (vi > vmax) vmax = vi;
+ }
+ int x = getSamplesPerLine();
+ int y = getNumberOfLines();
+ int[] multiples = new int[] {8, 16, 24, 32};
+ for (int i = 0; i < compSpecParams.length; i++) {
+ int[] compParam = compSpecParams[i];
+ int hi = compParam[1];
+ int vi = compParam[2];
+ int compWidth = (x * hi + hmax - 1) / hmax;
+ int compHeight = (y * vi + vmax - 1) / vmax;
+ int dsWidth = roundUpToMultiple(compWidth, multiples[hi - 1]);
+ int dsHeight = roundUpToMultiple(compHeight, multiples[vi - 1]);
+ compParam[3] = dsWidth;
+ compParam[4] = dsHeight;
+ }
+ setMaxHFactor(hmax);
+ setMaxVFactor(vmax);
+ }
+
+ int roundUpToMultiple(int anInteger, int mInteger) {
+ int a = anInteger + mInteger - 1;
+ return a - (a % mInteger);
+ }
+
+ /*
+ * Verify the information contained in the receiver is correct.
+ * Answer true if the header contains a valid marker. Otherwise,
+ * answer false. Valid Start Of Frame markers are:
+ * SOF_0 - Baseline DCT, Huffman coding
+ * SOF_1 - Extended sequential DCT, Huffman coding
+ * SOF_2 - Progressive DCT, Huffman coding
+ * SOF_3 - Lossless (sequential), Huffman coding
+ * SOF_5 - Differential sequential, Huffman coding
+ * SOF_6 - Differential progressive, Huffman coding
+ * SOF_7 - Differential lossless, Huffman coding
+ * SOF_9 - Extended sequential DCT, arithmetic coding
+ * SOF_10 - Progressive DCT, arithmetic coding
+ * SOF_11 - Lossless (sequential), arithmetic coding
+ * SOF_13 - Differential sequential, arithmetic coding
+ * SOF_14 - Differential progressive, arithmetic coding
+ * SOF_15 - Differential lossless, arithmetic coding
+ */
+ public boolean verify() {
+ int marker = getSegmentMarker();
+ return (marker >= JPEGFileFormat.SOF0 && marker <= JPEGFileFormat.SOF3) ||
+ (marker >= JPEGFileFormat.SOF5 && marker <= JPEGFileFormat.SOF7) ||
+ (marker >= JPEGFileFormat.SOF9 && marker <= JPEGFileFormat.SOF11) ||
+ (marker >= JPEGFileFormat.SOF13 && marker <= JPEGFileFormat.SOF15);
+ }
+
+ public boolean isProgressive() {
+ int marker = getSegmentMarker();
+ return marker == JPEGFileFormat.SOF2
+ || marker == JPEGFileFormat.SOF6
+ || marker == JPEGFileFormat.SOF10
+ || marker == JPEGFileFormat.SOF14;
+ }
+
+ public boolean isArithmeticCoding() {
+ return getSegmentMarker() >= JPEGFileFormat.SOF9;
+ }
+}

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