Add slice tool

Don't know if we want to add this but I found it useful when tracking down blur circle bugs.

Review URL: https://codereview.chromium.org/1350323002

1 files changed, 138 insertions, 0 deletions

diff --git a/tools/imgslice.cpp b/tools/imgslice.cpp
new file mode 100644
index 0000000000..e9e3832cd4
--- /dev/null
+++ b/tools/imgslice.cpp
@@ -0,0 +1,138 @@
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkCommandLineFlags.h"
+#include "SkImageDecoder.h"
+#include "SkStream.h"
+
+DEFINE_bool(header, false, "Print an extra row of the min-max values");
+DEFINE_string2(label, l, "label", "Label printed as the first value");
+
+DEFINE_string2(image, i, "", "Input image");
+DEFINE_int32_2(row, r, -1, "Row to extract");
+DEFINE_int32_2(column, c, -1, "Column to extract");
+
+DEFINE_int32_2(min, n, 0, "Minimum row/column to extract - inclusive");
+DEFINE_int32_2(max, m, 100, "Maximum row/column to extract - inclusive");
+
+DEFINE_int32(rgb, 0, "Color channel to print (0->b, 1->g, 2->r, 3->a)");
+
+DEFINE_bool2(quiet, q, false, "Quiet");
+DEFINE_bool2(reverse, v, false, "Iterate from max to min");
+
+
+// This tool just loads a single image and prints out a comma-separated row or column
+// Return codes:
+static const int kSuccess = 0;
+static const int kError = 1;
+
+int tool_main(int argc, char** argv);
+int tool_main(int argc, char** argv) {
+    SkCommandLineFlags::SetUsage("Print out a row or column of an image.");
+    SkCommandLineFlags::Parse(argc, argv);
+
+    if (FLAGS_rgb > 3 || FLAGS_rgb < 0) {
+        if (!FLAGS_quiet) {
+            SkDebugf("Channel (--rgb) must be between 0 and 3 (inclusive) - value is %d.\n",
+                     FLAGS_rgb);
+        }
+        return kError;        
+    }
+
+    if (FLAGS_row >= 0 && FLAGS_column >= 0) {
+        if (!FLAGS_quiet) {
+            SkDebugf("Only one of '-c' or '-r' can be specified at at time.\n");
+        }
+        return kError;       
+    }
+
+    if (FLAGS_row < 0 && FLAGS_column < 0) {
+        if (!FLAGS_quiet) {
+            SkDebugf("At least one of '-c' or '-r' need to be specified.\n");
+        }
+        return kError;       
+    }
+
+    SkFILEStream inputStream(FLAGS_image[0]);
+    if (!inputStream.isValid()) {
+        if (!FLAGS_quiet) {
+            SkDebugf("Couldn't open file: %s\n", FLAGS_image[0]);
+        }
+        return kError;
+    }
+
+    SkAutoTDelete<SkImageDecoder> codec(SkImageDecoder::Factory(&inputStream));
+    if (!codec) {
+        if (!FLAGS_quiet) {
+            SkDebugf("Couldn't create codec for: %s.\n", FLAGS_image[0]);
+        }
+        return kError;
+    }
+
+    SkBitmap bitmap;
+
+    inputStream.rewind();
+    codec->decode(&inputStream, &bitmap, kN32_SkColorType, SkImageDecoder::kDecodePixels_Mode);
+
+    int top, bottom, left, right;
+
+    if (-1 != FLAGS_row) {
+        SkASSERT(-1 == FLAGS_column);
+
+        top = bottom = SkTPin(FLAGS_row, 0, bitmap.height()-1);
+        FLAGS_min = left = SkTPin(FLAGS_min, 0, bitmap.width()-1);
+        FLAGS_max = right = SkTPin(FLAGS_max, left, bitmap.width()-1);
+    } else {
+        SkASSERT(-1 != FLAGS_column);
+        left = right = SkTPin(FLAGS_column, 0, bitmap.width()-1);
+        FLAGS_min = top = SkTPin(FLAGS_min, 0, bitmap.height()-1);
+        FLAGS_max = bottom = SkTPin(FLAGS_max, top, bitmap.height()-1);
+    }
+
+    if (FLAGS_header) {
+        SkDebugf("header");
+        if (FLAGS_reverse) {
+            for (int i = FLAGS_max; i >= FLAGS_min; --i) {
+                SkDebugf(", %d", i);
+            }
+        } else {
+            for (int i = FLAGS_min; i <= FLAGS_max; ++i) {
+                SkDebugf(", %d", i);
+            }
+        }
+        SkDebugf("\n");
+    }
+
+    SkDebugf("%s", FLAGS_label[0]);
+    if (FLAGS_reverse) {
+        for (int y = bottom; y >= top; --y) {
+            for (int x = right; x >= left; --x) {
+                SkColor c = bitmap.getColor(x, y);
+
+                SkDebugf(", %d", ((c) >> (FLAGS_rgb*8)) & 0xFF);
+            }
+        }
+    } else {
+        for (int y = top; y <= bottom; ++y) {
+            for (int x = left; x <= right; ++x) {
+                SkColor c = bitmap.getColor(x, y);
+
+                SkDebugf(", %d", ((c) >> (FLAGS_rgb*8)) & 0xFF);
+            }
+        }        
+    }
+
+    SkDebugf("\n");
+
+    return kSuccess;
+}
+
+#if !defined SK_BUILD_FOR_IOS
+int main(int argc, char * const argv[]) {
+    return tool_main(argc, (char**) argv);
+}
+#endif