multiplex4 (m4) is a compressed file hence has a small capacity. And can store multi IQ data simultaneously (sample 4bit)

m4formatprototype.py

import struct

def create_multiplex4_file(filename, sample_rate, data_format, data_streams):
    with open(filename, 'wb') as file:
        # Write header information
        header = struct.pack('!If', sample_rate, data_format)
        file.write(header)

        # Write data streams
        for stream_data in data_streams:
            metadata = struct.pack('!I', stream_data['id'])  # Example: Stream ID
            file.write(metadata)

            # Write IQ data for each stream
            for iq_sample in stream_data['iq_data']:
                iq_byte = struct.pack('!B', iq_sample)  # Pack the 4-bit IQ sample into a byte
                file.write(iq_byte)


def read_multiplex4_file(file_path):
    with open(file_path, 'rb') as file:
        # Read header information
        header = file.read(8)  # Assuming header is 8 bytes long (4 bytes for sample rate, 4 bytes for format)
        sample_rate, data_format = struct.unpack('!If', header)

        data_streams = []

        # Read data streams
        while True:
            metadata = file.read(4)  # Assuming metadata is 4 bytes long (e.g., stream ID)
            if not metadata:
                break  # Reached the end of the file

            stream_id = struct.unpack('!I', metadata)[0]  # Extract the stream ID

            iq_data = []
            while True:
                iq_byte = file.read(1)  # Assuming each IQ sample is represented by 1 byte (8 bits)
                if not iq_byte:
                    break  # Reached the end of the current data stream

                iq_sample = struct.unpack('!B', iq_byte)[0]  # Unpack the byte as a single 4-bit IQ sample
                iq_data.append(iq_sample)

            data_streams.append({'id': stream_id, 'iq_data': iq_data})

    for stream_data in data_streams:
        iq = '|'.join([str(num) for num in stream_data['iq_data']])
    iqlist = iq.split("|0|0|0")
    iqdi = []
    for id, iqidremove in enumerate(iqlist):
        if id == 0:
            iqdi.append(iqidremove)
        else:
            iqdi.append(iqidremove[3:])
    iqdi2 = []
    for iqreplace in iqdi:
        iqdi2.append(iqreplace.replace('|', ','))
    iqpr = [list(map(int, item.split(','))) for item in iqdi2]
    data_streams = []
    for id, iq in enumerate(iqpr):
        data_streams.append({
            'id': id,
            'iq_data': iq
        })

    return sample_rate, data_format, data_streams

# Usage example
sample_rate = 1000000  # Example: 1 MHz
data_format = 2  # Example: 1 for complex float
data_streams = [
    {
        'id': 0,  # Example: Stream ID 1
        'iq_data': [1, 2, 3, 4, 5, 6]  # Example: List of 4-bit IQ samples
    },
    {
        'id': 1,  # Example: Stream ID 2
        'iq_data': [7, 8, 9, 10, 11, 12]  # Example: List of 4-bit IQ samples
    },
    {
        'id': 2,  # Example: Stream ID 3
        'iq_data': [13, 14, 15, 16, 17, 18]  # Example: List of 4-bit IQ samples
    },
    {
        'id': 3,  # Example: Stream ID 4
        'iq_data': [19, 20]  # Example: List of 4-bit IQ samples
    }
    # Add more data streams if needed
]
file_path = 'file.m4'  # Path to the .m4 file

create_multiplex4_file(file_path, sample_rate, data_format, data_streams)

# Usage example
sample_rate, data_format, data_streams = read_multiplex4_file(file_path)

# Print the retrieved data
print(f"Sample Rate: {sample_rate}")
print(f"Data Format: {data_format}")
for stream_data in data_streams:
    print(f"IQ Data for ID {stream_data['id']}: {stream_data['iq_data']}")

print("---------------------------")

# Select data for a specific ID
selected_id = 0  # Replace with the desired stream ID
selected_data = None

for stream_data in data_streams:
    if stream_data['id'] == selected_id:
        selected_data = stream_data['iq_data']
        break

# Print the selected data
if selected_data is not None:
    print(f"IQ Data for ID {selected_id}: {selected_data}")
else:
    print(f"No data found for ID {selected_id}")

regism4file.reg

Windows Registry Editor Version 5.00

[HKEY_CLASSES_ROOT\.m4]
"Content Type"="sample/m4"
@="Multiplex4"

here this is output

Sample Rate: 1000000
Data Format: 2.0
IQ Data for ID 0: [1, 2, 3, 4, 5, 6]
IQ Data for ID 1: [7, 8, 9, 10, 11, 12]
IQ Data for ID 2: [13, 14, 15, 16, 17, 18]
IQ Data for ID 3: [19, 20]
---------------------------
IQ Data for ID 0: [1, 2, 3, 4, 5, 6]