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ComputerVisionClient Error or Bug - ReadInStreamAsync method: 'Invalid URI format' in Xamarin.Forms

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评估

难度
3/5
预计耗时
1-2 天
新手友好度
35/100
Issue 类型
缺陷
描述清晰度
基本清楚
活跃度
停滞
技术栈
csharp
领域
computer-vision, mobile-dev

调研方向

该 issue 未指定任何仓库文件或测试；从 Xamarin.Forms 对 ComputerVisionClient.ReadInStreamAsync 的调用以及报告的 stream.Name 值开始。使用提供的 MediaPicker stream 重现 Invalid URI 错误，然后验证 OCR 能读取图像并返回文本，且不会出现该异常。

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描述

Please provide us with the following information:

This issue is for a: (mark with an x)
- [x ] bug report -> please search issues before submitting
- [ ] feature request
- [ ] documentation issue or request
- [ ] regression (a behavior that used to work and stopped in a new release)
Minimal steps to reproduce

I am capturing a photo and opening a stream using Xamarin.Essentials 1.7 MediaPicker built into Essentials.
When I call the ReadInStreamAsync(stream) method in Computer Vision Client, I get an error and my Xamarin.Forms app breaks inside the method: 'Invalid URI: The format of the URI could not be determined.'
This is the stream.Name value - '/data/user/0/com.companyname.xamphotoappdemo2/cache/2203693cc04e0be7f4f024d5f9499e13/198fd32db9cc4be38a493325974fa138/d964251252fc4963aca94339d73a8007.jpg'

var stream = await file.OpenReadAsync();

chosenImage.Source = ImageSource.FromStream(() => stream);

// 2. Add OCR logic.

var client = Authenticate(ApiSettings.subscriptionKey, ApiSettings.endpoint);

var text = await client.ReadInStreamAsync(stream);

//after the request, get the operation location
string operationLocation = text.OperationLocation;

//we only need the operation ID, not the whole URL
const int numberOfCharsInOperationId = 36;
string operationId = operationLocation.Substring(operationLocation.Length - numberOfCharsInOperationId);

//Get the ocr read results
ReadOperationResult results;
do
{
results = await client.GetReadResultAsync(Guid.Parse(operationId));
}
while ((results.Status == OperationStatusCodes.Running || results.Status == OperationStatusCodes.NotStarted));

var readResults = results.AnalyzeResult.ReadResults;

var expirationDates = from page in readResults
from line in page.Lines
where line.Text.Contains("EXPIRES") && line.Words.Count == 4
select line.Words[3].Text;

expirationDate.Text = expirationDates.ToString();

Any log messages given by the failure
Expected/desired behavior

The text should be read in from the image and display on the Xaml page control.

OS and Version?

Windows 7, 8 or 10. Linux (which distribution). macOS (Yosemite? El Capitan? Sierra?)

Versions
Mention any other details that might be useful

Thanks! We'll be in touch soon.

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30 天内没有已合并 PR

环境准备

从这里开始

  1. 先读完整个 Issue，再读项目的贡献指南。
  2. 在 Issue 下留言说明你要接手 —— 这能避免两个人做同样的事。
  3. Fork 仓库，在一个分支上完成修改。
  4. 提交 Pull Request，并在描述里引用这个 Issue 编号。

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