Adding a tool to get images from skps

tools/get_images_from_skps.cpp

+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkCanvas.h"
+#include "SkCodec.h"
+#include "SkCommandLineFlags.h"
+#include "SkData.h"
+#include "SkOSFile.h"
+#include "SkPicture.h"
+#include "SkStream.h"
+
+DEFINE_string2(skps, s, "", "A path to a directory of skps.");
+DEFINE_string2(out, o, "", "A path to an output directory.");
+
+static int gCtr = 0;
+static int gSuccessCtr = 0;
+static int gFailureCtr = 0;
+static const char* gOutputDir;
+
+void setup_output_dirs() {
+    const char* exts[] = { "jpg", "png", "gif", "webp", "bmp", "wbmp", "ico", "dng", "unknown" };
+    for (const char* ext : exts) {
+        sk_mkdir(SkOSPath::Join(gOutputDir, ext).c_str());
+    }
+}
+
+bool store_encoded_to_file(const void* encoded, size_t length, SkBitmap* bitmap) {
+    // Silence warnings about empty bitmaps.
+    bitmap->allocN32Pixels(1, 1, true);
+
+    SkString path;
+    SkAutoTUnref<SkData> data(SkData::NewWithoutCopy(encoded, length));
+    SkAutoTDelete<SkCodec> codec(SkCodec::NewFromData(data));
+    if (codec) {
+        switch (codec->getEncodedFormat()) {
+            case SkEncodedFormat::kJPEG_SkEncodedFormat:
+                path = SkOSPath::Join(SkOSPath::Join(gOutputDir, "jpg").c_str(), "");
+                path.appendS32(gCtr++);
+                path.append(".jpg");
+                break;
+            case SkEncodedFormat::kPNG_SkEncodedFormat:
+                path = SkOSPath::Join(SkOSPath::Join(gOutputDir, "png").c_str(), "");
+                path.appendS32(gCtr++);
+                path.append(".png");
+                break;
+            case SkEncodedFormat::kGIF_SkEncodedFormat:
+                path = SkOSPath::Join(SkOSPath::Join(gOutputDir, "gif").c_str(), "");
+                path.appendS32(gCtr++);
+                path.append(".gif");
+                break;
+            case SkEncodedFormat::kWEBP_SkEncodedFormat:
+                path = SkOSPath::Join(SkOSPath::Join(gOutputDir, "webp").c_str(), "");
+                path.appendS32(gCtr++);
+                path.append(".webp");
+                break;
+            case SkEncodedFormat::kBMP_SkEncodedFormat:
+                path = SkOSPath::Join(SkOSPath::Join(gOutputDir, "bmp").c_str(), "");
+                path.appendS32(gCtr++);
+                path.append(".bmp");
+                break;
+            case SkEncodedFormat::kWBMP_SkEncodedFormat:
+                path = SkOSPath::Join(SkOSPath::Join(gOutputDir, "wbmp").c_str(), "");
+                path.appendS32(gCtr++);
+                path.append(".wbmp");
+                break;
+            case SkEncodedFormat::kICO_SkEncodedFormat:
+                path = SkOSPath::Join(SkOSPath::Join(gOutputDir, "ico").c_str(), "");
+                path.appendS32(gCtr++);
+                path.append(".ico");
+                break;
+            case SkEncodedFormat::kRAW_SkEncodedFormat:
+                path = SkOSPath::Join(SkOSPath::Join(gOutputDir, "dng").c_str(), "");
+                path.appendS32(gCtr++);
+                path.append(".dng");
+                break;
+            default:
+                path = SkOSPath::Join(gOutputDir, "unknown");
+                path.appendS32(gCtr++);
+                break;
+        }
+    } else {
+        path = SkOSPath::Join(gOutputDir, "unknown");
+        path.appendS32(gCtr++);
+    }
+
+    FILE* file = sk_fopen(path.c_str(), kWrite_SkFILE_Flag);
+    if (file) {
+        sk_fwrite(encoded, length, file);
+        sk_fclose(file);
+        gSuccessCtr++;
+        return true;
+    }
+
+    gFailureCtr++;

[scroggo, 2016/02/12 21:53:27]

I guess "number of failures" is ambiguous - I was thinking the images for which
we did not create a codec (or the "default" case).

This number tells us the number of times the file system gave us trouble, which
may be interesting (the data we retrieved is not complete). But I think failures
to create codec (of one of the types we expect) is a sign of a deeper problem.

+    SkDebugf("Could not open %s\n", path.c_str());
+    return false;
+}
+
+int main(int argc, char** argv) {
+    SkCommandLineFlags::SetUsage(
+            "Usage: get_images_from_skps -s <dir of skps> -o <dir for output images>\n");
+
+    SkCommandLineFlags::Parse(argc, argv);
+    if (FLAGS_skps.isEmpty() || FLAGS_out.isEmpty()) {
+        SkCommandLineFlags::PrintUsage();
+        return 1;
+    }
+
+    const char* inputs = FLAGS_skps[0];
+    gOutputDir = FLAGS_out[0];
+    if (!sk_isdir(inputs) || !sk_isdir(gOutputDir)) {
+        SkCommandLineFlags::PrintUsage();
+        return 1;
+    }
+
+    setup_output_dirs();
+    SkOSFile::Iter iter(inputs, "skp");
+    for (SkString file; iter.next(&file); ) {
+        SkAutoTDelete<SkStream> stream =
+                SkStream::NewFromFile(SkOSPath::Join(inputs, file.c_str()).c_str());
+
+        // Rather than passing in a function that actually decodes the encoded data,
+        // we pass in a function that saves the encoded data to a file.
+        SkAutoTUnref<SkPicture> picture(SkPicture::CreateFromStream(stream, store_encoded_to_file));
+
+        SkCanvas canvas;
+        canvas.drawPicture(picture);
+    }
+
+    SkDebugf("Saved %d images to %s\n", gSuccessCtr, gOutputDir);
+    SkDebugf("Failed on %d images\n", gFailureCtr);
+    return 0;
+}