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Diffstat (limited to 'jni_jpegstream/src/jpeg_writer.h')
-rw-r--r-- | jni_jpegstream/src/jpeg_writer.h | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/jni_jpegstream/src/jpeg_writer.h b/jni_jpegstream/src/jpeg_writer.h new file mode 100644 index 000000000..bd9a42d32 --- /dev/null +++ b/jni_jpegstream/src/jpeg_writer.h @@ -0,0 +1,83 @@ +/* + * 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_ |