GIF to C conversion program

gif2c.c

#include <stdio.h>      // standard input / output functions
// This program converts a GIF file into a C header file for the 
// POV Cylinder (https://www.instructables.com/id/POV-Cylinder-With-Arduino-Due/)
// 
// Author: Harald Bauer
// Date:   2015-04-17

//-----------------------------------------------------------------------------
  void convert_gif_file(const char *inFileName, const char *outFileName, const char *arrayName)
//-----------------------------------------------------------------------------
{
#define MAXFILESIZE 200001
    static unsigned char fileData[MAXFILESIZE];
    size_t fileSize;
    size_t i;
    FILE *fpIn, *fpOut;
    char s1[64], s2[64], s3[64];
    
    fpIn = fopen(inFileName, "rb");
    if (fpIn==NULL) {
        fprintf(stderr, "Command aborted - File '%s' not found\n", inFileName);
        return;
    }

    fpOut = fopen(outFileName, "wb");
    if (fpOut==NULL) {
        fprintf(stderr, "Error opening file %s\n", outFileName);
        return;
    }

    fileSize = fread(fileData, 1, MAXFILESIZE, fpIn);
    fclose(fpIn);

    if (fileSize>=MAXFILESIZE) {
        fprintf(stderr, "Command aborted - Files size is greater than %d bytes\n", MAXFILESIZE-1);
        return;
    }

    if (fileSize==0) {
        fprintf(stderr, "Command aborted - Error reading file\n");
        return;
    }
    fprintf(stderr, "Converting file %s - %lu bytes\n", inFileName, fileSize);
    //     { "Dog",            sizeof(gif_dog),             gif_dog,              0, 0 },
    sprintf(s1,"\"%s\",",     arrayName);
    sprintf(s2,"sizeof(%s),", arrayName);
    sprintf(s3,"%s,", arrayName);
    printf("    { %-20s %-25s %-18s 0, 0 },\n", s1, s2, s3);

    fprintf(fpOut, "// GIF File: %s\n", inFileName);
    fprintf(fpOut, "static const unsigned char %s[%lu] PROGMEM = {\n", arrayName, fileSize);
    fprintf(fpOut, "  0x%02X", fileData[0]);
    for (i=1; i<fileSize; i++) {
        if (i&15) fprintf(fpOut, ",0x%02X", fileData[i]);
        else fprintf(fpOut, ",\n  0x%02X", fileData[i]);
    }
    fprintf(fpOut, "\n};\n");
    fclose(fpOut);
}

//-----------------------------------------------------------------------------
  int main (int argc, char *argv[])
//-----------------------------------------------------------------------------
{
    fprintf(stderr, "GIF to C conversion program\n");
    
    if (argc != 4) fprintf(stderr, "Usage: gif2c <infile> <outfile> <arrayname>\n");
    else convert_gif_file(argv[1], argv[2], argv[3]);

    return 0;
}