satdump/src-core/common/codings/soft_reader.h

#pragma once

#include "pipeline/module.h"

namespace satdump
{
    class SoftSymbolReader
    {
    private:
        std::istream &data_in;
        std::shared_ptr<dsp::RingBuffer<uint8_t>> &input_fifo;
        pipeline::ModuleDataType &input_data_type;
        bool convert_from_hard = false;

        int tmp_hard_buff_pos = 0;
        uint8_t *tmp_hard_buff;

        void readMore()
        {
            if (input_data_type == pipeline::DATA_FILE)
                data_in.read((char *)tmp_hard_buff, 1024);
            else
                input_fifo->read((uint8_t *)tmp_hard_buff, 1024);
            tmp_hard_buff_pos = 0;
        }

    public:
        SoftSymbolReader(std::istream &data_in, std::shared_ptr<dsp::RingBuffer<uint8_t>> &input_fifo, pipeline::ModuleDataType &input_data_type, const nlohmann::json &params)
            : data_in(data_in), input_fifo(input_fifo), input_data_type(input_data_type)
        {
            if (params.contains("hard_symbols"))
                convert_from_hard = params["hard_symbols"];

            if (convert_from_hard)
                tmp_hard_buff = new uint8_t[1024];
        }

        ~SoftSymbolReader()
        {
            if (convert_from_hard)
                delete[] tmp_hard_buff;
        }

        inline void readSoftSymbols(int8_t *buffer, int length)
        {
            if (convert_from_hard)
            {
                for (int i = 0; i < length; i++)
                {
                    uint8_t bit = (tmp_hard_buff[tmp_hard_buff_pos / 8] >> (7 - (tmp_hard_buff_pos % 8))) & 1;
                    buffer[i] = bit ? 70 : -70;
                    tmp_hard_buff_pos++;
                    if (tmp_hard_buff_pos == 1024 * 8)
                        readMore();
                }
            }
            else
            {
                if (input_data_type == pipeline::DATA_FILE)
                    data_in.read((char *)buffer, length);
                else
                    input_fifo->read((uint8_t *)buffer, length);
            }
        }
    };
} // namespace satdump