Adding YUVImage and YUVCanvas.

YUVImage is a container class to hold YUV data and provide
various utilities, e.g. to set/get pixel values for different
YUV formats, fast copying routines, etc.
Currently supported YUV420 Planar and YUV420 Semi Planar.

YUVCanvas holds a reference to a YUVImage on which it can do various
drawing operations.

Change-Id: I052a57b7fbc834efe1626914f76c04c091996cac

2 files changed, 241 insertions, 0 deletions

diff --git a/include/media/stagefright/YUVCanvas.h b/include/media/stagefright/YUVCanvas.h
new file mode 100644
index 0000000..5e17046
--- /dev/null
+++ b/include/media/stagefright/YUVCanvas.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// YUVCanvas holds a reference to a YUVImage on which it can do various
+// drawing operations. It provides various utility functions for filling,
+// cropping, etc.
+
+
+#ifndef YUV_CANVAS_H_
+
+#define YUV_CANVAS_H_
+
+#include <stdint.h>
+
+namespace android {
+
+class YUVImage;
+class Rect;
+
+class YUVCanvas {
+public:
+
+    // Constructor takes in reference to a yuvImage on which it can do
+    // various drawing opreations.
+    YUVCanvas(YUVImage &yuvImage);
+    ~YUVCanvas();
+
+    // Fills the entire image with the given YUV values.
+    void FillYUV(uint8_t yValue, uint8_t uValue, uint8_t vValue);
+
+    // Fills the rectangular region [startX,endX]x[startY,endY] with the given YUV values.
+    void FillYUVRectangle(const Rect& rect,
+            uint8_t yValue, uint8_t uValue, uint8_t vValue);
+
+    // Copies the region [startX,endX]x[startY,endY] from srcImage into the
+    // canvas' target image (mYUVImage) starting at
+    // (destinationStartX,destinationStartY).
+    // Note that undefined behavior may occur if srcImage is same as the canvas'
+    // target image.
+    void CopyImageRect(
+            const Rect& srcRect,
+            int32_t destStartX, int32_t destStartY,
+            const YUVImage &srcImage);
+
+private:
+    YUVImage& mYUVImage;
+
+    YUVCanvas(const YUVCanvas &);
+    YUVCanvas &operator=(const YUVCanvas &);
+};
+
+}  // namespace android
+
+#endif  // YUV_CANVAS_H_
diff --git a/include/media/stagefright/YUVImage.h b/include/media/stagefright/YUVImage.h
new file mode 100644
index 0000000..afeac3f
--- /dev/null
+++ b/include/media/stagefright/YUVImage.h
@@ -0,0 +1,174 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// A container class to hold YUV data and provide various utilities,
+// e.g. to set/get pixel values.
+// Supported formats:
+//  - YUV420 Planar
+//  - YUV420 Semi Planar
+//
+//  Currently does not support variable strides.
+//
+//  Implementation: Two simple abstractions are done to simplify access
+//  to YUV channels for different formats:
+//  - initializeYUVPointers() sets up pointers (mYdata, mUdata, mVdata) to
+//  point to the right start locations of the different channel data depending
+//  on the format.
+//  - getOffsets() returns the correct offset for the different channels
+//  depending on the format.
+//  Location of any pixel's YUV channels can then be easily computed using these.
+//
+
+#ifndef YUV_IMAGE_H_
+
+#define YUV_IMAGE_H_
+
+#include <stdint.h>
+#include <cstring>
+
+namespace android {
+
+class Rect;
+
+class YUVImage {
+public:
+    // Supported YUV formats
+    enum YUVFormat {
+        YUV420Planar,
+        YUV420SemiPlanar
+    };
+
+    // Constructs an image with the given size, format. Also allocates and owns
+    // the required memory.
+    YUVImage(YUVFormat yuvFormat, int32_t width, int32_t height);
+
+    // Constructs an image with the given size, format. The memory is provided
+    // by the caller and we don't own it.
+    YUVImage(YUVFormat yuvFormat, int32_t width, int32_t height, uint8_t *buffer);
+
+    // Destructor to delete the memory if it owns it.
+    ~YUVImage();
+
+    // Returns the size of the buffer required to store the YUV data for the given
+    // format and geometry. Useful when the caller wants to allocate the requisite
+    // memory.
+    static size_t bufferSize(YUVFormat yuvFormat, int32_t width, int32_t height);
+
+    int32_t width() {return mWidth;}
+    int32_t height() {return mHeight;}
+
+    // Get the pixel YUV value at pixel (x,y).
+    // Note that the range of x is [0, width-1] and the range of y is [0, height-1].
+    // Returns true if get was succesful and false otherwise.
+    bool getPixelValue(int32_t x, int32_t y,
+            uint8_t *yPtr, uint8_t *uPtr, uint8_t *vPtr) const;
+
+    // Set the pixel YUV value at pixel (x,y).
+    // Note that the range of x is [0, width-1] and the range of y is [0, height-1].
+    // Returns true if set was succesful and false otherwise.
+    bool setPixelValue(int32_t x, int32_t y,
+            uint8_t yValue, uint8_t uValue, uint8_t vValue);
+
+    // Uses memcpy to copy an entire row of data
+    static void fastCopyRectangle420Planar(
+            const Rect& srcRect,
+            int32_t destStartX, int32_t destStartY,
+            const YUVImage &srcImage, YUVImage &destImage);
+
+    // Uses memcpy to copy an entire row of data
+    static void fastCopyRectangle420SemiPlanar(
+            const Rect& srcRect,
+            int32_t destStartX, int32_t destStartY,
+            const YUVImage &srcImage, YUVImage &destImage);
+
+    // Tries to use memcopy to copy entire rows of data.
+    // Returns false if fast copy is not possible for the passed image formats.
+    static bool fastCopyRectangle(
+            const Rect& srcRect,
+            int32_t destStartX, int32_t destStartY,
+            const YUVImage &srcImage, YUVImage &destImage);
+
+    // Convert the given YUV value to RGB.
+    void yuv2rgb(uint8_t yValue, uint8_t uValue, uint8_t vValue,
+        uint8_t *r, uint8_t *g, uint8_t *b) const;
+
+    // Write the image to a human readable PPM file.
+    // Returns true if write was succesful and false otherwise.
+    bool writeToPPM(const char *filename) const;
+
+private:
+    // YUV Format of the image.
+    YUVFormat mYUVFormat;
+
+    int32_t mWidth;
+    int32_t mHeight;
+
+    // Pointer to the memory buffer.
+    uint8_t *mBuffer;
+
+    // Boolean telling whether we own the memory buffer.
+    bool mOwnBuffer;
+
+    // Pointer to start of the Y data plane.
+    uint8_t *mYdata;
+
+    // Pointer to start of the U data plane. Note that in case of interleaved formats like
+    // YUV420 semiplanar, mUdata points to the start of the U data in the UV plane.
+    uint8_t *mUdata;
+
+    // Pointer to start of the V data plane. Note that in case of interleaved formats like
+    // YUV420 semiplanar, mVdata points to the start of the V data in the UV plane.
+    uint8_t *mVdata;
+
+    // Initialize the pointers mYdata, mUdata, mVdata to point to the right locations for
+    // the given format and geometry.
+    // Returns true if initialize was succesful and false otherwise.
+    bool initializeYUVPointers();
+
+    // For the given pixel location, this returns the offset of the location of y, u and v
+    // data from the corresponding base pointers -- mYdata, mUdata, mVdata.
+    // Note that the range of x is [0, width-1] and the range of y is [0, height-1].
+    // Returns true if getting offsets was succesful and false otherwise.
+    bool getOffsets(int32_t x, int32_t y,
+        int32_t *yOffset, int32_t *uOffset, int32_t *vOffset) const;
+
+    // Returns the offset increments incurred in going from one data row to the next data row
+    // for the YUV channels. Note that this corresponds to data rows and not pixel rows.
+    // E.g. depending on formats, U/V channels may have only one data row corresponding
+    // to two pixel rows.
+    bool getOffsetIncrementsPerDataRow(
+        int32_t *yDataOffsetIncrement,
+        int32_t *uDataOffsetIncrement,
+        int32_t *vDataOffsetIncrement) const;
+
+    // Given the offset return the address of the corresponding channel's data.
+    uint8_t* getYAddress(int32_t offset) const;
+    uint8_t* getUAddress(int32_t offset) const;
+    uint8_t* getVAddress(int32_t offset) const;
+
+    // Given the pixel location, returns the address of the corresponding channel's data.
+    // Note that the range of x is [0, width-1] and the range of y is [0, height-1].
+    bool getYUVAddresses(int32_t x, int32_t y,
+        uint8_t **yAddr, uint8_t **uAddr, uint8_t **vAddr) const;
+
+    // Disallow implicit casting and copying.
+    YUVImage(const YUVImage &);
+    YUVImage &operator=(const YUVImage &);
+};
+
+}  // namespace android
+
+#endif  // YUV_IMAGE_H_