Segmentation fault at IMGENC1_process

I have the following function (see below) in my program and it gives me segmentation fault when calling IMGENC1_process. The function is called as follows:

        MakeYUV2JPEG("/mnt/ram/image.jpeg", display_buffers[2].user_addr,  2048, 1536, 75, display_buffers[0].user_addr);

where:

    display_buffers[2].user_addr is pointing to a (2048*1536*2+4096 bytes) buffer (allocated by CMEM)

    display_buffers[0].user_addr is pointing to a (1056*1536*4+4096 bytes) buffer (allocated by CMEM)

What could be the cause of segmentation fault?

Thank you.

====== my function =====

int MakeYUV2JPEG(char * filename, void * ptr, int width, int height, int Q, void * tmpbuf)
{
    Engine_Handle ceh;
    Engine_Error cerr;
    IMGENC1_Handle ieh;
    IIMGENC1_Params params;
    IIMGENC1_DynamicParams dynamicparams;
    IMGENC1_Status status;
    IIMGENC1_InArgs inargs;
    IIMGENC1_OutArgs outargs;
    FILE * afile;
   
    int res, i;

    params.size = sizeof(params);
   
    // init Code Engine (run-time variables)
    CERuntime_init();

    // open codec engine
    ceh = Engine_open("imgenc1_copy", NULL, &cerr);
    if (!ceh)
    {
        switch(cerr)
        {
            case Engine_EOK: printf("Open success\n"); break;
            case Engine_EEXIST: printf("Open name does not exist\n"); break;
            case Engine_ENOMEM: printf("Open can't allocate memory\n"); break;
            case Engine_EDSPLOAD: printf("Open can't load the DSP\n"); break;
            case Engine_ENOCOMM: printf("Open can't create a comm connection to DSP\n"); break;
            case Engine_ENOSERVER: printf("Open can't locate the server on the DSP\n"); break;
            case Engine_ECOMALLOC: printf("Open can't allocate communication buffer\n"); break;
            default: printf("Open error undefined\n");
        }
        CERuntime_exit();
        return -1;
    }
   
    // create JPEG encoder instance
    ieh = IMGENC1_create(ceh, "jpegenc", NULL);
    if (!ieh)
    {
        printf("Failed to create jpegenc instance\n");
        Engine_close(ceh);   
        CERuntime_exit();
        return -1;
    }

    dynamicparams.size = sizeof(dynamicparams);
    dynamicparams.numAU = XDM_DEFAULT;     // number of Access units to encode.
                        // (if want to feed the data in chunks to save buffer space)
    dynamicparams.inputChromaFormat = XDM_YUV_422P;    // format of the input data. see enum XDM_ChromaFormat for all formats
    dynamicparams.inputHeight = height;
    dynamicparams.inputWidth = width;
    dynamicparams.captureWidth = 0; // set to zero to use image width. don't know what it's for.
    dynamicparams.generateHeader = XDM_ENCODE_AU; // don't knwo what it's for but this is what dvtb used.
    dynamicparams.qValue = Q; // compress JPEG qith quality = 75%
   
    memset(&status, 0, sizeof(status));
    status.size = sizeof(status); // define the size of status structure

    res = IMGENC1_control(ieh, XDM_SETPARAMS, &dynamicparams, &status);
    if (res != IMGENC1_EOK)
    {
        printf("Error (%d), Extended Error (%d) in image Encoder Control:setparams\n", res, status.extendedError);
        IMGENC1_delete(ieh);
        Engine_close(ceh);   
        CERuntime_exit();
        return -1;
    }
    printf("CE params set OK\n");

    memset(&status, 0, sizeof(status));
    status.size = sizeof(status); // define the size of status structure
    res = IMGENC1_control(ieh, XDM_GETBUFINFO, &dynamicparams, &status);
    if (res != IMGENC1_EOK)
    {
        printf("Error (%d), Extended Error (%d) in image Encoder Control: getbufinfo\n", res, status.extendedError);
        IMGENC1_delete(ieh);
        Engine_close(ceh);   
        CERuntime_exit();
        return -1;
    }   
   
   
    printf("Input buffers needed: %d\n",(int)status.bufInfo.minNumInBufs);
    for(i=0;i<status.bufInfo.minNumInBufs;i++)
        printf("Input buffer %d size: %d\n",i, (int)status.bufInfo.minInBufSize[i]);

    printf("Output buffers needed: %d\n",(int)status.bufInfo.minNumOutBufs);
    for(i=0;i<status.bufInfo.minNumOutBufs;i++)
        printf("Output buffer %d size: %d\n",i, (int)status.bufInfo.minOutBufSize[i]);

    inargs.size = sizeof(inargs);
    outargs.size = sizeof(outargs);
   
    res = IMGENC1_process(ieh, ptr, tmpbuf, &inargs, &outargs) ;
    if (res != IMGENC1_EOK)
    {
        printf("Error encoding image\n");
        IMGENC1_delete(ieh);
        Engine_close(ceh);   
        CERuntime_exit();
        return -1;
    }
    printf("JPEG encoded: %d bytes\n",outargs.bytesGenerated);

    if ((afile = fopen(filename,"w")))
    {
        fwrite(tmpbuf, outargs.bytesGenerated, 1, afile);
        fclose(afile);
    }
   
    IMGENC1_delete(ieh);
   
    Engine_close(ceh);   

    CERuntime_exit();
    return 0;
}
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