I am trying to decompress LZO-compressed data in Python using the lzo library. While the same compressed data is successfully decompressed in C++ using the lzo1z_decompress function, the equivalent Python implementation with lzo.decompress throws the following error:

lzoERR: Header error - invalid compressed data
Decompression failed: Header error - invalid compressed data

What I have tried Here is the C++ code snippet that works perfectly for decompression:

void PacketParser(char* rawBuffer)
{   
    short maxPktSize = 506, headerOffset = 8;
    int offsetRaw = 0;
    int offsetData = 0;
    int dataLen = 0;    
    int cNetId = (int)((rawBuffer+offsetRaw)[0]);
    offsetRaw += 2;
   
    short iNoPackets=0;
    memcpy(&iNoPackets, rawBuffer+offsetRaw, 2);
    offsetRaw += 2;
    iNoPackets = ntohs(iNoPackets);
    for(int t = 0; t < iNoPackets; t++)
    {
        short iCompLen = 0;
        memcpy(&iCompLen, rawBuffer+offsetRaw, 2);
        offsetRaw += 2;
        iCompLen = ntohs(iCompLen);
        if(iCompLen>0)
        {
            int lzoOutSize = 4096;
            int lzoERR, lzoERRCount=0;
            ///Decompress using LZO
            lzo_uint i_len = (lzo_uint)iCompLen;         
            lzo_uint o_len = (lzo_uint)-1;    
            lzo_byte i_buff[1024];
            lzo_memset(i_buff,0,1024);
            memcpy(i_buff, rawBuffer+offsetRaw, iCompLen);       
            if (i_buff == NULL) return;
            offsetRaw += iCompLen;
            lzo_byte o_buff[4096];
            lzo_memset(o_buff,0, 4096);
            lzoERR = lzo1z_decompress(i_buff,i_len,o_buff,&o_len,NULL);
            if(lzoERR!=0)
            {
                cout<<"lzoERR:"<<lzoERR<<endl;              
                return;
            }
            else
            {           
                memcpy(dataBuffer+offsetData,o_buff,o_len);
            }
            dataLen = o_len;
        }
        else
            memcpy(dataBuffer+offsetData, rawBuffer+offsetRaw, maxPktSize);
        //parsing data here
    }
}

The Python equivalent implementation is as follows:

def PacketParser(rawBuffer):
    print(f"Raw Buffer Compressed data (hex): {rawBuffer.hex()}")
    offsetRaw = 0
    cNetId = int(rawBuffer[offsetRaw])
    offsetRaw += 2
    print(f"cNetId|{cNetId}")
    iNoPackets = struct.unpack('!H', rawBuffer[offsetRaw:offsetRaw + 2])[0]
    offsetRaw += 2
    print(f"iNoPackets|{iNoPackets}")
    iCompLen = struct.unpack('!H', rawBuffer[offsetRaw:offsetRaw + 2])[0]
    offsetRaw += 2
    print(f"iCompLenFirst|{iCompLen}")
    i_buff = rawBuffer[offsetRaw:offsetRaw + iCompLen]
    offsetRaw += iCompLen
    print(f"Compressed data (hex): {i_buff.hex()}")
    try:
        decompressed_data = lzo.decompress(i_buff)
        print(f"Decompressed Data: {decompressed_data}")
    except lzo.error as e:
        print(f"Decompression failed: {e}")

Observations

The Python code prints the compressed data as a hexadecimal string, which matches the expected input. Despite this, lzo.decompress consistently throws the header error.

Question

What am I doing wrong in the Python code? Is there any specific way to handle lzo1z_decompress behavior in Python? How can I achieve error-free decompression of this data using Python?