esp-idf/components/esp_driver_jpeg/private/jpeg_param.h

44 lines
1.2 KiB
C

/*
* SPDX-FileCopyrightText: 2024 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
#pragma once
#include <stdint.h>
#include "driver/jpeg_types.h"
#include "../jpeg_private.h"
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief Zigzag scan pattern array.
*
* This array represents a zigzag scan pattern for reordering the coefficients
* in a block of data. It is commonly used in JPEG compression and decompression
* algorithms to optimize encoding and decoding processes.
*
* The array consists of 64 elements, where each element represents the position
* of a coefficient in the zigzag pattern. The coefficients are traversed in the
* order specified by this array to achieve efficient compression and decompression.
*
* @note The values in this array are zero-indexed.
*/
extern const uint8_t zigzag_arr[64];
/**
* @brief DMA2D best hb value table for JPEG decompression.
*
* This two-dimensional array represents a Huffman decoding table for JPEG
* decompression. It is used to decode the Huffman-coded symbols in the compressed
* data stream during the decoding process.
*/
extern const uint32_t dec_hb_tbl[JPEG_DOWN_SAMPLING_MAX][JPEG_DEC_BEST_HB_MAX];
#ifdef __cplusplus
}
#endif