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+/*
+ * Copyright (C) 2013 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.
+ */
+#ifndef JPEG_WRITER_H_
+#define JPEG_WRITER_H_
+
+#include "jerr_hook.h"
+#include "jni_defines.h"
+#include "jpeg_config.h"
+
+#include <stdint.h>
+
+/**
+ * JpegWriter wraps libjpeg's compression functionality and a
+ * java OutputStream object. Write calls result in input data
+ * being compressed and written to the OuputStream.
+ */
+class JpegWriter {
+public:
+ JpegWriter();
+ ~JpegWriter();
+
+ /**
+ * Call setup with a valid OutputStream reference, bitmap height and
+ * width, pixel format, and compression quality in range (0, 100].
+ *
+ * Returns J_SUCCESS on success or a negative error code.
+ */
+ int32_t setup(JNIEnv *env, jobject out, int32_t width, int32_t height,
+ Jpeg_Config::Format format, int32_t quality);
+
+ /**
+ * Compresses bytes from the input buffer.
+ *
+ * ***This method will result in bytes being written to the OutputStream***
+ *
+ * Returns J_SUCCESS on success or a negative error code.
+ */
+ int32_t write(int8_t* bytes, int32_t length);
+
+ /**
+ * Updates the environment pointer. Call this before write or reset
+ * in any jni function call.
+ */
+ void updateEnv(JNIEnv *env);
+
+ /**
+ * Frees any java global references held by the JpegWriter, destroys
+ * the compress structure, and frees allocations in libjpeg's pools.
+ */
+ int32_t reset();
+
+ static const int32_t DEFAULT_X_DENSITY;
+ static const int32_t DEFAULT_Y_DENSITY;
+ static const int32_t DEFAULT_DENSITY_UNIT;
+private:
+ void formatPixels(uint8_t* buf, int32_t len);
+ struct jpeg_compress_struct mInfo;
+ ErrManager mErrorManager;
+
+ JSAMPLE* mScanlineBuf;
+ JSAMPLE* mScanlineIter;
+ int32_t mScanlineBuflen;
+ int32_t mScanlineBytesRemaining;
+
+ Jpeg_Config::Format mFormat;
+ bool mFinished;
+ bool mSetup;
+};
+
+#endif // JPEG_WRITER_H_