1 files changed, 112 insertions, 0 deletions
diff --git a/common/image_pnm.cpp b/common/image_pnm.cpp
new file mode 100644
index 0000000..5397a1a
--- /dev/null
+++ b/common/image_pnm.cpp
@@ -0,0 +1,112 @@
+/**************************************************************************
+ *
+ * Copyright 2011 Jose Fonseca
+ * Copyright 2008-2010 VMware, Inc.
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ **************************************************************************/
+
+
+#include <assert.h>
+#include <string.h>
+#include <stdint.h>
+
+#include "image.hpp"
+
+
+namespace Image {
+
+/**
+ * http://en.wikipedia.org/wiki/Netpbm_format
+ * http://netpbm.sourceforge.net/doc/ppm.html
+ */
+void
+Image::writePNM(std::ostream &os, const char *comment) const {
+    assert(channels == 1 || channels >= 3);
+
+    os << (channels == 1 ? "P5" : "P6") << "\n";
+    if (comment) {
+        os << "#" << comment << "\n";
+    }
+    os << width << " " << height << "\n";
+    os << "255" << "\n";
+
+    const unsigned char *row;
+
+    if (channels == 1 || channels == 3) {
+        for (row = start(); row != end(); row += stride()) {
+            os.write((const char *)row, width*channels);
+        }
+    } else {
+        unsigned char *tmp = new unsigned char[width*3];
+        if (channels == 4) {
+            for (row = start(); row != end(); row += stride()) {
+                const uint32_t *src = (const uint32_t *)row;
+                uint32_t *dst = (uint32_t *)tmp;
+                unsigned x;
+                for (x = 0; x + 4 <= width; x += 4) {
+                    /*
+                     * It's much faster to access dwords than bytes.
+                     *
+                     * FIXME: Big-endian version.
+                     */
+
+                    uint32_t rgba0 = *src++ & 0xffffff;
+                    uint32_t rgba1 = *src++ & 0xffffff;
+                    uint32_t rgba2 = *src++ & 0xffffff;
+                    uint32_t rgba3 = *src++ & 0xffffff;
+                    uint32_t rgb0 = rgba0
+                                  | (rgba1 << 24);
+                    uint32_t rgb1 = (rgba1 >> 8)
+                                  | (rgba2 << 16);
+                    uint32_t rgb2 = (rgba2 >> 16)
+                                  | (rgba3 << 8);
+                    *dst++ = rgb0;
+                    *dst++ = rgb1;
+                    *dst++ = rgb2;
+                }
+                for (; x < width; ++x) {
+                    tmp[x*3 + 0] = row[x*4 + 0];
+                    tmp[x*3 + 1] = row[x*4 + 1];
+                    tmp[x*3 + 2] = row[x*4 + 2];
+                }
+                os.write((const char *)tmp, width*3);
+            }
+        } else if (channels == 2) {
+            for (row = start(); row != end(); row += stride()) {
+                const unsigned char *src = row;
+                unsigned char *dst = tmp;
+                for (unsigned x = 0; x < width; ++x) {
+                    *dst++ = *src++;
+                    *dst++ = *src++;
+                    *dst++ = 0;
+                }
+                os.write((const char *)tmp, width*3);
+            }
+        } else {
+            assert(0);
+        }
+        delete [] tmp;
+    }
+}
+
+
+} /* namespace Image */