使用 Google Drive 在 Android 中集成 OCR
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【中文标题】使用 Google Drive 在 Android 中集成 OCR【英文标题】：OCR integration in Android using Google Drive 【发布时间】：2013-04-20 04:09:27 【问题描述】：我搜索了很多，但我还没有成功。我不想使用 Tesseract 方法。
我已经根据
创建了项目https://developers.google.com/drive/quickstart-android
在运行时，图像被上传到了 goggle docs 。我收到了文件上传成功的消息，文件名为 .
用于下载我关注的数据
public void downloadfile(File file)
String imageAsTextUrl = file.getExportLinks().get("text/plain");
HttpClient client = new DefaultHttpClient();
HttpGet get = new HttpGet(imageAsTextUrl);
HttpResponse response;
StringBuffer sb = new StringBuffer();
BufferedReader in = null;
try
response = client.execute(get);
in = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
String str;
while ((str = in.readLine()) != null)
sb.append(str);
Log.e(" sb data ", sb.toString());
in.close();
catch (ClientProtocolException e)
e.printStackTrace();
catch (IOException e)
e.printStackTrace();
我得到了返回数据
" <!DOCTYPE html><html lang="en"> <head> <meta charset="utf-8"> <title>Welcome to Google Docs</title><style type="text/css"> html, body, div, h1, h2, h3, h4, h5, h6, p, img, dl, dt, dd, ol, ul, li, table, tr, td, form, object, embed, article, aside, canvas, command, details, fieldset, figcaption, figure, footer, group, header, hgroup, legend, mark, menu, meter, nav, output, progress, section, summary, time, audio, video margin: 0; padding: 0; border: 0; article, aside, details, figcaption, figure, footer, header, hgroup, menu, nav, section display: block; html font: 81.25% arial, helvetica, sans-serif; background: #fff; color: #333; line-height: 1; direction: ltr; a color: #15c; text-decoration: none; a:active color: #d14836; a:hover text-decoration: underline; h1, h2, h3, h4, h5, h6 color: #222; font-size: 1.54em; font-weight: normal; line-height: 24px; margin: 0 0 .46em; p line-height: 17px; margin: 0 0 1em; ol, ul list-style: none; line-height: 17px; margin: 0 0 1em; li margin: 0 0 .5em; table border-collapse: collapse; border-spacing: 0; strong color: #222; </style><style type="text/css"> html, body position: absolute; height: 100%; min-width: 100%; .wrapper position: relative; min-height: 100%; .wrapper + style + iframe display: none; .content padding: 0 44px; .topbar text-align: right; padding-top: .5em; padding-bottom: .5em; .google-header-bar height: 71px; background: #f1f1f1; border-bottom: 1px solid #e5e5e5; overflow: hidden; .header .logo margin: 17px 0 0; float: left; .header .signin, .header .signup margin: 28px 0 0; float: right; font-weight: bold; .header .signin-button, .header .signup-button margin: 22px 0 0; float: right; .header .signin-button a font-size: 13px; font-weight: normal; .header .signup-button a position: relative; top: -1px; margin: 0 0 0 1em; .main margin: 0 auto; width: 650px; padding-top: 23px; padding-bottom: 100px; .main h1:first-child margin: 0 0 .92em; .google-footer-bar position: absolute; bottom: 0; height: 35px; width: 100%; border-top: 1px solid #ebebeb; overflow: hidden; .footer padding-top: 9px; font-size: .85em; white-space: nowrap; line-height: 0; .footer ul color: #999; float: left; max-width: 80%; .footer ul li display: inline; padding: 0 1.5em 0 0; .footer a color: #333; .footer .lang-chooser-wrap float: right; max-width: 20%; .footer .lang-chooser-wrap img vertical-align: middle; .footer .attribution float: right; .footer .attribution span vertical-align: text-top; .redtext color: #dd4b39; .greytext color: #555; .secondary font-size: 11px; color: #666; .source color: #093; .hidden display: none; .announce-bar position: absolute; bottom: 35px; height: 33px; z-index: 2; width: 100%; background: #f9edbe; border-top: 1px solid #efe1ac; border-bottom: 1px solid #efe1ac; overflow: hidden; .announce-bar .message font-size: .85em; line-height: 33px; margin: 0; .announce-bar .message .separated margin-left: 1.5em; .announce-bar-ac background: #eee; border-top: 1px solid #e5e5e5; border-bottom: 1px solid #e5e5e5; .clearfix:after visibility: hidden; display: block; font-size: 0; content: '.'; clear: both; height: 0; * html .clearfix zoom: 1; *:first-child+html .clearfix zoom: 1; pre font-family: monospace; position: absolute; left: 0; margin: 0; padding: 1.5em; font-size: 13px; background: #f1f1f1; border-top: 1px solid #e5e5e5; direction: ltr; </style><style type="text/css"> button, input, select, textarea font-family: inherit; font-size: inherit; button::-moz-focus-inner, input::-moz-focus-inner border: 0; input[type=email], input[type=number], input[type=password], input[type=tel], input[type=text], input[type=url] -webkit- "
但这不会返回图片中的文字，我上传了。如何获取文本，我作为图片上传？
当我尝试时
Android Open and Save files to/from Google Drive SDK
下载时出现错误
“DriveRequest driveRequest = (DriveRequest) request;”
它无法将 HttpRequest 转换为 DriveRequest
然后我尝试了
DriveRequest driveRequest = DriveRequest.class.cast(request);
但是我在说 ClassCastExcaption 的那一行中遇到了崩溃。
欢迎任何相关答案。提前致谢。
【问题讨论】：
【参考方案1】：我的答案是正确的添加
get.setHeader("Authorization", "Bearer " + credential.getToken());
到downloadfile 方法。
由于我的身份验证不正确，它返回了 Google Docs 欢迎页面的 HTML。添加这一行后，我得到了正确识别的文本。
【讨论】：
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