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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_
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