get_img.h

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#pragma once

 
#include "image/image.h"
#include "logger.h"
#include "xrit/identify.h"
#include "xrit/xrit_file.h"
 
#include "xrit/fy4/fy4_headers.h"
 
namespace satdump
{
    namespace xrit
    {
        inline image::Image getImageFromXRITFile(xrit_file_type_t type, XRITFile &file)
        {
            PrimaryHeader primary_header = file.getHeader<PrimaryHeader>();
 
            if (!file.hasHeader<ImageStructureRecord>())
            {
                logger->error("Tried to parse XRIT image but no image header!");
                return image::Image();
            }
 
            if (type == XRIT_FY4_AGRI)
            {
                logger->trace("Using FY-4x Specific Image Header!");
                fy4::ImageInformationRecord image_structure_record = file.getHeader<fy4::ImageInformationRecord>(); //(&lrit_data[all_headers[ImageStructureRecord::TYPE]]);
 
                size_t required_buffer_size = (image_structure_record.bit_per_pixel > 8 ? 2 : 1) * image_structure_record.columns_count * image_structure_record.lines_count;
                if (required_buffer_size <= file.lrit_data.size() - primary_header.total_header_length)
                {
                    image::Image image(&file.lrit_data[primary_header.total_header_length], image_structure_record.bit_per_pixel > 8 ? 16 : 8, image_structure_record.columns_count,
                                       image_structure_record.lines_count, 1);
 
                    return image;
                }
                else
                {
                    logger->error("File is an image but the file is too small!");
                    return image::Image();
                }
            }
            else
            {
                ImageStructureRecord image_structure_record = file.getHeader<ImageStructureRecord>(); //(&lrit_data[all_headers[ImageStructureRecord::TYPE]]);
 
                size_t required_buffer_size = (image_structure_record.bit_per_pixel > 8 ? 2 : 1) * image_structure_record.columns_count * image_structure_record.lines_count;
                if (required_buffer_size <= file.lrit_data.size() - primary_header.total_header_length)
                {
                    image::Image image(&file.lrit_data[primary_header.total_header_length], image_structure_record.bit_per_pixel > 8 ? 16 : 8, image_structure_record.columns_count,
                                       image_structure_record.lines_count, 1);
 
                    if (type == XRIT_HIMAWARI_AHI)
                    {
                        if (image_structure_record.bit_per_pixel == 16)
                        {
                            // Special case as Himawari sends it in Big Endian...?
                            image::Image image2(16, image_structure_record.columns_count, image_structure_record.lines_count, 1);
 
                            for (long long int i = 0; i < image_structure_record.columns_count * image_structure_record.lines_count; i++)
                                image2.set(i, ((&file.lrit_data[primary_header.total_header_length])[i * 2 + 0] << 8 | (&file.lrit_data[primary_header.total_header_length])[i * 2 + 1]));
 
                            image = image2;
 
                            if (image2.get(0) >= 16383)
                            {
                                // Needs to be shifted up by 2
                                for (long long int i = 0; i < image_structure_record.columns_count * image_structure_record.lines_count; i++)
                                    image.set(i, image.get(i) << 2);
                            }
                            else if (image2.get(0) >= 4095)
                            {
                                // Needs to be shifted up by 4
                                for (long long int i = 0; i < image_structure_record.columns_count * image_structure_record.lines_count; i++)
                                    image.set(i, image.get(i) << 4);
                            }
                            else
                            {
                                // Needs to be shifted up by 6
                                for (long long int i = 0; i < image_structure_record.columns_count * image_structure_record.lines_count; i++)
                                    image.set(i, image.get(i) << 6);
                            }
                        }
                    }
 
                    return image;
                }
                else
                {
                    logger->error("File is an image but the file is too small!");
                    return image::Image();
                }
            }
        }
 
    } // namespace xrit
} // namespace satdump