ImageLoadingTransformer hides exceptions in Mapper.MakeGetter #3154

Open
Open
ImageLoadingTransformer hides exceptions in Mapper.MakeGetter#3154
Labels
P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request

Description

@mareklinka
mareklinka
opened on Apr 1, 2019

System information

  • OS version/distro: Windows 10 1809
  • .NET Version (eg., dotnet --info): 2.2.202

Issue

I recently tried to use ML.NET in a Xamarin-based UWP app. I targeted the earliest version of UWP that support .NET Standard 2.0 and everything installed correctly. My intention was to make use a separately-trained TensorFlow model to predict some data from an image.

While my code worked without issues in a .NET Core 2.2 console app, in the UWP it was failing. I was constantly getting an exception when attempting to load the target image - Image [whatever] was not found. No additional details, no inner exception.

Only after a fair amount of headscratching and trying various things I managed to find the culprit (which was obvious in hindsight): UWP does not support bitmaps. After I tried to replicate a little bit of the ImageLoader code, I got an unsupported platform exception.

This is all fair but then looking into the code some more, I found this:

machinelearning/src/Microsoft.ML.ImageAnalytics/ImageLoader.cs

Line 215 in b5a8d99

throwHost.Except($"Image {src.ToString()} was not found.");

The code is catching all exceptions and throwing a custom exception in their place, without providing the base exception. I think this could be improved as part of making the API surface friendlier to use - spending an hour on this, I started to think I was doing something insanely wrong. The inner exception would have told me the root cause in 10 seconds flat.

So there are basically two issues:

  1. Hiding the base exceptions
  2. Image analytics won't work in UWP at all because of bitmaps

I think a fix for 1. could be relatively simple. 2. will be much more difficult and might not be desirable but I wanted to throw it out there. Maybe using a platform-agnostic implementation of image handling could be useful.

Opinions? Thoughts?

Metadata

Metadata

Assignees

No one assigned

    Labels

    P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request

    Type

    No type

    Projects

    No projects

      Milestone

      No milestone

      Relationships

      None yet

      Development

      No branches or pull requests

      Issue actions

      , 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
       blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

      Skip to content
      ImageLoadingTransformer hides exceptions in Mapper.MakeGetter #3154
      Open
      Open
      ImageLoadingTransformer hides exceptions in Mapper.MakeGetter#3154
      Labels
      P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request
      Description
      @mareklinka
      mareklinka
      opened on Apr 1, 2019
      System information
      • OS version/distro: Windows 10 1809
      • .NET Version (eg., dotnet --info): 2.2.202
      Issue
      I recently tried to use ML.NET in a Xamarin-based UWP app. I targeted the earliest version of UWP that support .NET Standard 2.0 and everything installed correctly. My intention was to make use a separately-trained TensorFlow model to predict some data from an image.
      While my code worked without issues in a .NET Core 2.2 console app, in the UWP it was failing. I was constantly getting an exception when attempting to load the target image - Image [whatever] was not found. No additional details, no inner exception.
      Only after a fair amount of headscratching and trying various things I managed to find the culprit (which was obvious in hindsight): UWP does not support bitmaps. After I tried to replicate a little bit of the ImageLoader code, I got an unsupported platform exception.
      This is all fair but then looking into the code some more, I found this:
      machinelearning/src/Microsoft.ML.ImageAnalytics/ImageLoader.cs
      
Line 215
in
b5a8d99
      throwHost.Except($"Image {src.ToString()} was not found.");
      The code is catching all exceptions and throwing a custom exception in their place, without providing the base exception. I think this could be improved as part of making the API surface friendlier to use - spending an hour on this, I started to think I was doing something insanely wrong. The inner exception would have told me the root cause in 10 seconds flat.
      So there are basically two issues:
      1. Hiding the base exceptions
      2. Image analytics won't work in UWP at all because of bitmaps
      I think a fix for 1. could be relatively simple. 2. will be much more difficult and might not be desirable but I wanted to throw it out there. Maybe using a platform-agnostic implementation of image handling could be useful.
      Opinions? Thoughts?
      Metadata
      Metadata
      Assignees
      No one assigned
        Labels
        P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request
        Type
        No type
        Projects
        No projects
          Milestone
          No milestone
          Relationships
          None yet
          Development
          No branches or pull requests
          Issue actions
          
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

          Skip to content
          ImageLoadingTransformer hides exceptions in Mapper.MakeGetter #3154
          Open
          Open
          ImageLoadingTransformer hides exceptions in Mapper.MakeGetter#3154
          Labels
          P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request
          Description
          @mareklinka
          mareklinka
          opened on Apr 1, 2019
          System information
          • OS version/distro: Windows 10 1809
          • .NET Version (eg., dotnet --info): 2.2.202
          Issue
          I recently tried to use ML.NET in a Xamarin-based UWP app. I targeted the earliest version of UWP that support .NET Standard 2.0 and everything installed correctly. My intention was to make use a separately-trained TensorFlow model to predict some data from an image.
          While my code worked without issues in a .NET Core 2.2 console app, in the UWP it was failing. I was constantly getting an exception when attempting to load the target image - Image [whatever] was not found. No additional details, no inner exception.
          Only after a fair amount of headscratching and trying various things I managed to find the culprit (which was obvious in hindsight): UWP does not support bitmaps. After I tried to replicate a little bit of the ImageLoader code, I got an unsupported platform exception.
          This is all fair but then looking into the code some more, I found this:
          machinelearning/src/Microsoft.ML.ImageAnalytics/ImageLoader.cs
          
Line 215
in
b5a8d99
          throwHost.Except($"Image {src.ToString()} was not found.");
          The code is catching all exceptions and throwing a custom exception in their place, without providing the base exception. I think this could be improved as part of making the API surface friendlier to use - spending an hour on this, I started to think I was doing something insanely wrong. The inner exception would have told me the root cause in 10 seconds flat.
          So there are basically two issues:
          1. Hiding the base exceptions
          2. Image analytics won't work in UWP at all because of bitmaps
          I think a fix for 1. could be relatively simple. 2. will be much more difficult and might not be desirable but I wanted to throw it out there. Maybe using a platform-agnostic implementation of image handling could be useful.
          Opinions? Thoughts?
          Metadata
          Metadata
          Assignees
          No one assigned
            Labels
            P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request
            Type
            No type
            Projects
            No projects
              Milestone
              No milestone
              Relationships
              None yet
              Development
              No branches or pull requests
              Issue actions
              
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

              Skip to content
              ImageLoadingTransformer hides exceptions in Mapper.MakeGetter #3154
              Open
              Open
              ImageLoadingTransformer hides exceptions in Mapper.MakeGetter#3154
              Labels
              P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request
              Description
              @mareklinka
              mareklinka
              opened on Apr 1, 2019
              System information
              • OS version/distro: Windows 10 1809
              • .NET Version (eg., dotnet --info): 2.2.202
              Issue
              I recently tried to use ML.NET in a Xamarin-based UWP app. I targeted the earliest version of UWP that support .NET Standard 2.0 and everything installed correctly. My intention was to make use a separately-trained TensorFlow model to predict some data from an image.
              While my code worked without issues in a .NET Core 2.2 console app, in the UWP it was failing. I was constantly getting an exception when attempting to load the target image - Image [whatever] was not found. No additional details, no inner exception.
              Only after a fair amount of headscratching and trying various things I managed to find the culprit (which was obvious in hindsight): UWP does not support bitmaps. After I tried to replicate a little bit of the ImageLoader code, I got an unsupported platform exception.
              This is all fair but then looking into the code some more, I found this:
              machinelearning/src/Microsoft.ML.ImageAnalytics/ImageLoader.cs
              
Line 215
in
b5a8d99
              throwHost.Except($"Image {src.ToString()} was not found.");
              The code is catching all exceptions and throwing a custom exception in their place, without providing the base exception. I think this could be improved as part of making the API surface friendlier to use - spending an hour on this, I started to think I was doing something insanely wrong. The inner exception would have told me the root cause in 10 seconds flat.
              So there are basically two issues:
              1. Hiding the base exceptions
              2. Image analytics won't work in UWP at all because of bitmaps
              I think a fix for 1. could be relatively simple. 2. will be much more difficult and might not be desirable but I wanted to throw it out there. Maybe using a platform-agnostic implementation of image handling could be useful.
              Opinions? Thoughts?
              Metadata
              Metadata
              Assignees
              No one assigned
                Labels
                P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request
                Type
                No type
                Projects
                No projects
                  Milestone
                  No milestone
                  Relationships
                  None yet
                  Development
                  No branches or pull requests
                  Issue actions
                  
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

                  Skip to content
                  ImageLoadingTransformer hides exceptions in Mapper.MakeGetter #3154
                  Open
                  Open
                  ImageLoadingTransformer hides exceptions in Mapper.MakeGetter#3154
                  Labels
                  P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request
                  Description
                  @mareklinka
                  mareklinka
                  opened on Apr 1, 2019
                  System information
                  • OS version/distro: Windows 10 1809
                  • .NET Version (eg., dotnet --info): 2.2.202
                  Issue
                  I recently tried to use ML.NET in a Xamarin-based UWP app. I targeted the earliest version of UWP that support .NET Standard 2.0 and everything installed correctly. My intention was to make use a separately-trained TensorFlow model to predict some data from an image.
                  While my code worked without issues in a .NET Core 2.2 console app, in the UWP it was failing. I was constantly getting an exception when attempting to load the target image - Image [whatever] was not found. No additional details, no inner exception.
                  Only after a fair amount of headscratching and trying various things I managed to find the culprit (which was obvious in hindsight): UWP does not support bitmaps. After I tried to replicate a little bit of the ImageLoader code, I got an unsupported platform exception.
                  This is all fair but then looking into the code some more, I found this:
                  machinelearning/src/Microsoft.ML.ImageAnalytics/ImageLoader.cs
                  
Line 215
in
b5a8d99
                  throwHost.Except($"Image {src.ToString()} was not found.");
                  The code is catching all exceptions and throwing a custom exception in their place, without providing the base exception. I think this could be improved as part of making the API surface friendlier to use - spending an hour on this, I started to think I was doing something insanely wrong. The inner exception would have told me the root cause in 10 seconds flat.
                  So there are basically two issues:
                  1. Hiding the base exceptions
                  2. Image analytics won't work in UWP at all because of bitmaps
                  I think a fix for 1. could be relatively simple. 2. will be much more difficult and might not be desirable but I wanted to throw it out there. Maybe using a platform-agnostic implementation of image handling could be useful.
                  Opinions? Thoughts?
                  Metadata
                  Metadata
                  Assignees
                  No one assigned
                    Labels
                    P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request
                    Type
                    No type
                    Projects
                    No projects
                      Milestone
                      No milestone
                      Relationships
                      None yet
                      Development
                      No branches or pull requests
                      Issue actions
                      
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

                      Skip to content
                      ImageLoadingTransformer hides exceptions in Mapper.MakeGetter #3154
                      Open
                      Open
                      ImageLoadingTransformer hides exceptions in Mapper.MakeGetter#3154
                      Labels
                      P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request
                      Description
                      @mareklinka
                      mareklinka
                      opened on Apr 1, 2019
                      System information
                      • OS version/distro: Windows 10 1809
                      • .NET Version (eg., dotnet --info): 2.2.202
                      Issue
                      I recently tried to use ML.NET in a Xamarin-based UWP app. I targeted the earliest version of UWP that support .NET Standard 2.0 and everything installed correctly. My intention was to make use a separately-trained TensorFlow model to predict some data from an image.
                      While my code worked without issues in a .NET Core 2.2 console app, in the UWP it was failing. I was constantly getting an exception when attempting to load the target image - Image [whatever] was not found. No additional details, no inner exception.
                      Only after a fair amount of headscratching and trying various things I managed to find the culprit (which was obvious in hindsight): UWP does not support bitmaps. After I tried to replicate a little bit of the ImageLoader code, I got an unsupported platform exception.
                      This is all fair but then looking into the code some more, I found this:
                      machinelearning/src/Microsoft.ML.ImageAnalytics/ImageLoader.cs
                      
Line 215
in
b5a8d99
                      throwHost.Except($"Image {src.ToString()} was not found.");
                      The code is catching all exceptions and throwing a custom exception in their place, without providing the base exception. I think this could be improved as part of making the API surface friendlier to use - spending an hour on this, I started to think I was doing something insanely wrong. The inner exception would have told me the root cause in 10 seconds flat.
                      So there are basically two issues:
                      1. Hiding the base exceptions
                      2. Image analytics won't work in UWP at all because of bitmaps
                      I think a fix for 1. could be relatively simple. 2. will be much more difficult and might not be desirable but I wanted to throw it out there. Maybe using a platform-agnostic implementation of image handling could be useful.
                      Opinions? Thoughts?
                      Metadata
                      Metadata
                      Assignees
                      No one assigned
                        Labels
                        P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request
                        Type
                        No type
                        Projects
                        No projects
                          Milestone
                          No milestone
                          Relationships
                          None yet
                          Development
                          No branches or pull requests
                          Issue actions
                          
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

                          Skip to content
                          ImageLoadingTransformer hides exceptions in Mapper.MakeGetter #3154
                          Open
                          Open
                          ImageLoadingTransformer hides exceptions in Mapper.MakeGetter#3154
                          Labels
                          P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request
                          Description
                          @mareklinka
                          mareklinka
                          opened on Apr 1, 2019
                          System information
                          • OS version/distro: Windows 10 1809
                          • .NET Version (eg., dotnet --info): 2.2.202
                          Issue
                          I recently tried to use ML.NET in a Xamarin-based UWP app. I targeted the earliest version of UWP that support .NET Standard 2.0 and everything installed correctly. My intention was to make use a separately-trained TensorFlow model to predict some data from an image.
                          While my code worked without issues in a .NET Core 2.2 console app, in the UWP it was failing. I was constantly getting an exception when attempting to load the target image - Image [whatever] was not found. No additional details, no inner exception.
                          Only after a fair amount of headscratching and trying various things I managed to find the culprit (which was obvious in hindsight): UWP does not support bitmaps. After I tried to replicate a little bit of the ImageLoader code, I got an unsupported platform exception.
                          This is all fair but then looking into the code some more, I found this:
                          machinelearning/src/Microsoft.ML.ImageAnalytics/ImageLoader.cs
                          
Line 215
in
b5a8d99
                          throwHost.Except($"Image {src.ToString()} was not found.");
                          The code is catching all exceptions and throwing a custom exception in their place, without providing the base exception. I think this could be improved as part of making the API surface friendlier to use - spending an hour on this, I started to think I was doing something insanely wrong. The inner exception would have told me the root cause in 10 seconds flat.
                          So there are basically two issues:
                          1. Hiding the base exceptions
                          2. Image analytics won't work in UWP at all because of bitmaps
                          I think a fix for 1. could be relatively simple. 2. will be much more difficult and might not be desirable but I wanted to throw it out there. Maybe using a platform-agnostic implementation of image handling could be useful.
                          Opinions? Thoughts?
                          Metadata
                          Metadata
                          Assignees
                          No one assigned
                            Labels
                            P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request
                            Type
                            No type
                            Projects
                            No projects
                              Milestone
                              No milestone
                              Relationships
                              None yet
                              Development
                              No branches or pull requests
                              Issue actions
                              
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

                              Skip to content
                              ImageLoadingTransformer hides exceptions in Mapper.MakeGetter #3154
                              Open
                              Open
                              ImageLoadingTransformer hides exceptions in Mapper.MakeGetter#3154
                              Labels
                              P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request
                              Description
                              @mareklinka
                              mareklinka
                              opened on Apr 1, 2019
                              System information
                              • OS version/distro: Windows 10 1809
                              • .NET Version (eg., dotnet --info): 2.2.202
                              Issue
                              I recently tried to use ML.NET in a Xamarin-based UWP app. I targeted the earliest version of UWP that support .NET Standard 2.0 and everything installed correctly. My intention was to make use a separately-trained TensorFlow model to predict some data from an image.
                              While my code worked without issues in a .NET Core 2.2 console app, in the UWP it was failing. I was constantly getting an exception when attempting to load the target image - Image [whatever] was not found. No additional details, no inner exception.
                              Only after a fair amount of headscratching and trying various things I managed to find the culprit (which was obvious in hindsight): UWP does not support bitmaps. After I tried to replicate a little bit of the ImageLoader code, I got an unsupported platform exception.
                              This is all fair but then looking into the code some more, I found this:
                              machinelearning/src/Microsoft.ML.ImageAnalytics/ImageLoader.cs
                              
Line 215
in
b5a8d99
                              throwHost.Except($"Image {src.ToString()} was not found.");
                              The code is catching all exceptions and throwing a custom exception in their place, without providing the base exception. I think this could be improved as part of making the API surface friendlier to use - spending an hour on this, I started to think I was doing something insanely wrong. The inner exception would have told me the root cause in 10 seconds flat.
                              So there are basically two issues:
                              1. Hiding the base exceptions
                              2. Image analytics won't work in UWP at all because of bitmaps
                              I think a fix for 1. could be relatively simple. 2. will be much more difficult and might not be desirable but I wanted to throw it out there. Maybe using a platform-agnostic implementation of image handling could be useful.
                              Opinions? Thoughts?
                              Metadata
                              Metadata
                              Assignees
                              No one assigned
                                Labels
                                P2Priority of the issue for triage purpose: Needs to be fixed at some point.UWPBugs related UWPbugSomething isn't workingenhancementNew feature or request
                                Type
                                No type
                                Projects
                                No projects
                                  Milestone
                                  No milestone
                                  Relationships
                                  None yet
                                  Development
                                  No branches or pull requests
                                  Issue actions