背景说明

前段时间接了个项目说需要解决打印机的打印问题，而后通过厂家给出了CPCL指令集，第一反应是这是什么鬼，居然都是字符，为什么不是常见的ESC指令，后边通过dome和文档学习了一下，才明白，原来如此。

这是豆丁网的指令集文档，有兴趣的可以看看

本文将主要介绍CPCL指令打印位图的做法，着急的童鞋可以直接复制下面代码用。后边会详细说明这段代码的解释。

- (NSMutableString *)picToBitmbp:(UIImage *)image{
    NSInteger wid = image.size.width;
    NSInteger hid = image.size.height;
    NSMutableString *str = [[NSMutableString alloc] init];
    if ((wid % 8) > 0) {
        wid = image.size.width + (8 - wid % 8);
    else {
        wid = image.size.width;
    for (int y = 0; y < hid - 1; y++) {
        NSInteger bit = 128;
        NSInteger currentValue = 0;
        for (int x = 0; x < wid - 1; x++) {
            NSInteger intensity = 0;
            if (x < image.size.width) {
                intensity = [self getPixelColorAtLocation:CGPointMake(x, y) image:image];
            }else{
                intensity = 0;
            if (intensity >= 128) {
                currentValue |= bit;
                bit = bit >> 1;
            }else{
                currentValue &= ~bit;
                bit = bit >> 1;
            if (bit == 0) {
                [str appendFormat:@"%@",[self ToHex:currentValue]];
                bit = 128;
                currentValue = 0;
    return str;
-(NSString *)ToHex:(long long int)tmpid
    NSString *nLetterValue;
    NSString *str =@"";
    long long int ttmpig;
    for (int i = 0; i<17; i++) {
        ttmpig=tmpid%16;
        tmpid=tmpid/16;
        switch (ttmpig)
            case 10:
                nLetterValue =@"A";break;
            case 11:
                nLetterValue =@"B";break;
            case 12:
                nLetterValue =@"C";break;
            case 13:
                nLetterValue =@"D";break;
            case 14:
                nLetterValue =@"E";break;
            case 15:
                nLetterValue =@"F";break;
            default:nLetterValue=[[NSString alloc]initWithFormat:@"%lli",ttmpig];
        str = [nLetterValue stringByAppendingString:str];
        if (tmpid == 0) {
            break;  
    if (str.length == 1) {
        str = [NSString stringWithFormat:@"0%@",str];
    return str;
- (NSInteger) getPixelColorAtLocation:(CGPoint)point image:(UIImage*)image{
    UIColor* color = nil;
    NSInteger back;
    CGImageRef inImage = image.CGImage;
    // Create off screen bitmap context to draw the image into. Format ARGB is 4 bytes for each pixel: Alpa, Red, Green, Blue
    CGContextRef cgctx = [self createARGBBitmapContextFromImage:inImage];
    if (cgctx == NULL) {
        return nil; /* error */
    size_t w = CGImageGetWidth(inImage);
    size_t h = CGImageGetHeight(inImage);
    CGRect rect = {{0,0},{w,h}};
    // Draw the image to the bitmap context. Once we draw, the memory
    // allocated for the context for rendering will then contain the
    // raw image data in the specified color space.
    CGContextDrawImage(cgctx, rect, inImage);
    // Now we can get a pointer to the image data associated with the bitmap
    // context.
    unsigned char* data = CGBitmapContextGetData (cgctx);
    if (data != NULL) {
        //offset locates the pixel in the data from x,y.
        //4 for 4 bytes of data per pixel, w is width of one row of data.
        int offset = 4*((w*round(point.y))+round(point.x));
        int alpha =  data[offset];
        int red = data[offset+1];
        int green = data[offset+2];
        int blue = data[offset+3];
//        color = [UIColor colorWithRed:(red/255.0f) green:(green/255.0f) blue:(blue/255.0f) alpha:(alpha/255.0f)];
        if (alpha == 0) {
            back = 0;
        }else{
            back = 255 - (alpha + red + green + blue) / 4;
        NSLog(@"offset: %i colors: RGB A %i %i %i  %i  %lu",offset,red,green,blue,alpha,back);
    // When finished, release the context
    CGContextRelease(cgctx);
    // Free image data memory for the context
    if (data) { free(data); }
    return back;
- (CGContextRef) createARGBBitmapContextFromImage:(CGImageRef) inImage {
    CGContextRef    context = NULL;
    CGColorSpaceRef colorSpace;
    void *     bitmapData;
    int             bitmapByteCount;
    int             bitmapBytesPerRow;
    // Get image width, height. We'll use the entire image.
    size_t pixelsWide = CGImageGetWidth(inImage);
    size_t pixelsHigh = CGImageGetHeight(inImage);
    // Declare the number of bytes per row. Each pixel in the bitmap in this
    // example is represented by 4 bytes; 8 bits each of red, green, blue, and
    // alpha.
    bitmapBytesPerRow   = (pixelsWide * 4);
    bitmapByteCount     = (bitmapBytesPerRow * pixelsHigh);
    // Use the generic RGB color space.
    colorSpace = CGColorSpaceCreateDeviceRGB();
    if (colorSpace == NULL)
        fprintf(stderr, "Error allocating color space\n");
        return NULL;
    // Allocate memory for image data. This is the destination in memory
    // where any drawing to the bitmap context will be rendered.
    bitmapData = malloc( bitmapByteCount );
    if (bitmapData == NULL)
        fprintf (stderr, "Memory not allocated!");
        CGColorSpaceRelease( colorSpace );
        return NULL;
    // Create the bitmap context. We want pre-multiplied ARGB, 8-bits
    // per component. Regardless of what the source image format is
    // (CMYK, Grayscale, and so on) it will be converted over to the format
    // specified here by CGBitmapContextCreate.
    context = CGBitmapContextCreate (bitmapData,
                                     pixelsWide,
                                     pixelsHigh,
                                     8,      // bits per component
                                     bitmapBytesPerRow,
                                     colorSpace,
                                     kCGImageAlphaPremultipliedFirst);
    if (context == NULL)
        free (bitmapData);
        fprintf (stderr, "Context not created!");
    // Make sure and release colorspace before returning
    CGColorSpaceRelease( colorSpace );
    return context;
NSString *hex = [self picToBitmbp:image];

将上面大块代码复制回去，然后调用这一句即可获得图片的打印数据。

其次在这里还有个问题，这样是获取到了图片的数据，

CPCL打印图片的指令可不只是图片数据。