mirror of
https://github.com/STMicroelectronics/STM32CubeF4.git
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86 lines
2.8 KiB
C
86 lines
2.8 KiB
C
/**
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******************************************************************************
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* @file LibJPEG/LibJPEG_Encoding/Src/decode.c
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* @author MCD Application Team
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* @brief This file contains the decompress method.
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******************************************************************************
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* @attention
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*
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* <h2><center>© Copyright (c) 2017 STMicroelectronics.
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* All rights reserved.</center></h2>
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*
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* This software component is licensed by ST under Ultimate Liberty license
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* SLA0044, the "License"; You may not use this file except in compliance with
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* the License. You may obtain a copy of the License at:
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* www.st.com/SLA0044
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*
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******************************************************************************
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*/
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/* Includes ------------------------------------------------------------------*/
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#include "decode.h"
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/* Private typedef -----------------------------------------------------------*/
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/* This struct contains the JPEG decompression parameters */
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struct jpeg_decompress_struct cinfo;
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/* This struct represents a JPEG error handler */
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struct jpeg_error_mgr jerr;
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/* Private define ------------------------------------------------------------*/
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/* Private macro -------------------------------------------------------------*/
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/* Private variables ---------------------------------------------------------*/
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/* Private function prototypes -----------------------------------------------*/
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/* Private functions ---------------------------------------------------------*/
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/**
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* @brief Decode
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* @param callback:
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* @param file:
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* @param width:
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* @param buff:
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* @retval None
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*/
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void jpeg_decode(JFILE *file, uint32_t width, uint8_t * buff, uint8_t (*callback)(uint8_t*, uint32_t))
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{
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/* Decode JPEG Image */
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JSAMPROW buffer[2] = {0}; /* Output row buffer */
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uint32_t row_stride = 0; /* Physical row width in image buffer */
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buffer[0] = buff;
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/* Step 1: Allocate and initialize JPEG decompression object */
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cinfo.err = jpeg_std_error(&jerr);
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/* Step 2: Initialize the JPEG decompression object */
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jpeg_create_decompress(&cinfo);
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jpeg_stdio_src (&cinfo, file);
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/* Step 3: read image parameters with jpeg_read_header() */
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jpeg_read_header(&cinfo, TRUE);
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/* Step 4: set parameters for decompression */
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cinfo.dct_method = JDCT_FLOAT;
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/* Step 5: start decompressor */
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jpeg_start_decompress(&cinfo);
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row_stride = width * 3;
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while (cinfo.output_scanline < cinfo.output_height)
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{
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(void) jpeg_read_scanlines(&cinfo, buffer, 1);
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if (callback(buffer[0], row_stride) != 0)
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{
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break;
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}
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}
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/* Step 6: Finish decompression */
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jpeg_finish_decompress(&cinfo);
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/* Step 7: Release JPEG decompression object */
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jpeg_destroy_decompress(&cinfo);
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}
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/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
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