我希望在我的iPhone 应用中集成Google Docs OCR功能。以下是Google Docs文档的说明:
要对 .pdf、.jpg、.png 或 .gif 文件执行OCR,请在上传文件时包含 ocr=true 参数:
POST /feeds/default/private/full?ocr=true
GData-Version: 3.0
Authorization: <your authorization header here>
Content-Length: 1984
Content-Type: image/png
Slug: OCRd Doc
... png contents here ...
现在,我正在使用以下代码进行HTTP POST请求。
responseData = [[NSMutableData data] retain];
NSURL *url = [NSURL URLWithString:@"http://docs.google.com/feeds/default/private/full?ocr=true"];
UIImage *img = [UIImage imageNamed:@"Submit-top.png"];
NSData *data = UIImagePNGRepresentation(img);
int a = [data length];
NSString *imgLength = [NSString stringWithFormat:@"%d" ,a];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc]initWithURL:url];
[request setHTTPBody:data];
[request setHTTPMethod:@"POST"];
[request addValue:@"3.0" forHTTPHeaderField:@"GData-Version:"];
[request addValue:auth.accessToken forHTTPHeaderField:@"Authorization:"];
[request addValue:imgLength forHTTPHeaderField:@"Content-Length:"];
[request addValue:@"image/png" forHTTPHeaderField:@"Content-Type:"];
[request addValue:@"OCRd Doc" forHTTPHeaderField:@"Slug:"];
[[NSURLConnection alloc] initWithRequest:request delegate:self];
NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
NSString *str = [[NSString alloc] initWithData:returnData encoding:NSUTF8StringEncoding];
NSLog(@"%@", str);
但是我收到的响应状态码是400。