We can scan images from camera with Zxing.Net but are there any solution to scanning existent images (like in library) ?
ZXing can read existent images, its Decode method takes WritableBitmap as a parameter. So you can get the image from user library with PhotoChooserTask, get WritableBitmap and read it.
Using ZXing is demonstrated here: http://developer.nokia.com/community/wiki/Generating_and_scanning_barcodes_using_ZXing_on_Windows_Phone
_barcodeReader.Decode(_previewBuffer);
_previewBuffer in this case is WritableBitmap
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It's posible convert an image sequence (jpg, png) to .flv (or .mp4 instead), using AS3/AIR?
I'm developing an app. This app must record video on an Android tablet.
As the "CameraUI" class doesn't permit to put images/design over the camera capture, and I need to overlay branded design,
I'm trying to save a sequence of bitmaps using this Starling extension (Using this extension I can overlay desing and it's manage a good performance).
My idea is take the generated image sequence, convert it to video, and then to delete the original bitmap files.
Any idea?
Thanks.
Yes this is possible. FLV is an open format. Easiest way is to create raw flv. Otherwise you need to search for the proper compression (there are libraries online).
For the first one, there are a few very old posts, but I think the idea is the same. Few can be found here:
http://www.zeropointnine.com/blog/simpleflvwriteras-as3-class-to-create-flvs/
http://www.joristimmerman.be/wordpress/2008/12/18/flvrecorder-record-to-flv-using-air/
Try to search for 'flv recorder'. There are few out, even with compression and audio.
I have a Windows Store (Metro) application. I need to add support for scanning barcodes.
I tried using ZXing first. From what I was able to get working, you actually need to click and save an image for it to do the processing. There's no nice overlay of a red line "scanner" nor does it process a live feed. This isn't a very elegant solution. It works far better on Android. Basically, this won't work as I need a constant video and a constant search for a barcode to be in focus.
This blog (http://www.soulier.ch/?p=1275&lang=en) mentions that extrapolating a frame out of a WinRT video stream is not allowed in managed code which means I'd need to use C++.
So, are there any components out there that do this? Anything free or paid that I can get that would be written in C++ and can find and extrapolate a barcode? Learning C++ is not on my bucket list.
You can capture frames while displaying a preview with C# only. Here's an example control that does it:
https://winrtxamltoolkit.codeplex.com/SourceControl/latest#WinRTXamlToolkit/Controls/CameraCaptureControl/CameraCaptureControl.cs
Basically you need to create a MediaCapture object and associate it with a CaptureElement control to display the preview. Then you can use CapturePhotoToStreamAsync() to capture a frame to a stream of your selected encoding format and then have a go at it with your bar code reading code.
I made a lib for WinRT using ZXing & Imaging SDK.
It works well (but does not include any additional focus feature).
There is a lib and a sample app that you can try.
It works for barcodes and QRCode (barcode by default but just change the optional parameter in the scan function code to use QRCode)
I'm currently testing the downloadcache and this really looks great.
I have some questions regarding this plugin (I'm pretty new to C# and don't understand the full source code of the plugin):
1) ProgressView
I would like to show a progressview on the image until it has been loaded.
To do that, I need to be notified when the image is loaded.
In the "MvxImageViewLoader" I see there is an Action "afterImageChangeAction" (null by default).
However, I don't understand if and how I can access that Action from "MvxImageView"?
(how to set it)
2) Don't load old image
When using Tables or Cellectionviews in iOS, it's important to check if the URL has been changed before setting the image (because iOS reuses the objects). I looked at the source code of the downloadcache and I don't see this check.
However, in the "MvxDynamicImageHelper.cs" class, I see that when a new URL is set, it calls "ClearCurrentHttpImageRequest();" which removes the "update" Events.
So I assume this is enough to prevent that an image is set to the wrong UIImageView?
3) ImageCache size in (mega)bytes
The ImageCache does not have a property to define the mamiximum size (megabytes for example) of the persistent image store (on the HD). I prefer to use a maximum size in (mega)bytes instead of a maximum amount of files because the user will care more how much space an app takes instead of how many files are stored by the app.
I assume the easiest for me is to define a "TimeSpan PeriodSaveInterval" independent from the one in MvxFileDownloadCache to just check the size of the folder defined for the Image Cache or any other recommendations?
Is it dangerous for performance to scan the folder and calculate the size of all the images in a folder?
Regards,
Matt
1) ProgressView
I would like to show a progressview on the image until it has been loaded. To do that, I need to be notified when the image is loaded.
There is a DefaultImagePath which provides the path of an image that should be shown during loading.
But if you need a dynamic animation or other custom view, then afterImageChangeAction can be used
As you've seen, you can't do this in MvxImageView - the Action wasn't really a suitable candidate to be a bindable property so it wasn't exposed as a property.
However, you can:
do this by using MvxImageViewLoader directly in your View - there are several samples of using this in views in the N+1 samples - https://github.com/slodge/NPlus1DaysOfMvvmCross/search?q=MvxImageViewLoader
do this by creating your own MyImageView class - it's not a big class to write - https://github.com/slodge/MvvmCross/blob/v3/Cirrious/Cirrious.MvvmCross.Binding.Touch/Views/MvxImageView.cs
As an alternative to using the Action callback, you can also inherit from MvxBaseImageViewLoader<T> and provide an override for the ImageHelperOnImageChanged method - see https://github.com/slodge/MvvmCross/blob/v3/Cirrious/Cirrious.MvvmCross.Binding/Views/MvxBaseImageViewLoader.cs#L49
2) Don't load old image
3) ImageCache size in (mega)bytes
The interface-driven and plugin structure of MvvmCross is defined to allow you to implement alternatives.
In the case of loading images from HTTP, there are many alternatives - you don't have to use the MvvmCross download cache for image loading.
The only docs available for the download cache plugin currently is https://github.com/slodge/MvvmCross/wiki/MvvmCross-plugins#downloadcache
For Android, some suggestions for alternative implementations are listed in: https://github.com/slodge/MvvmCross/issues/416
For iOS, it may be useful to read https://developer.apple.com/library/ios/documentation/FileManagement/Conceptual/FileSystemProgrammingGuide/FileSystemOverview/FileSystemOverview.html including the section on <Application_Home>/Library/Caches
I know Stuart already provided an excellent answer. But what I did, when I needed the exact same feature, was to subclass MvxImageView and override the UIImageView.Image property. When the image is set I fire an event which is caught by the viewcontroller.
I don't know whether it's the right place to put this up. But I've been trying from past 12 hours and haven't found anything related.
I'm creating a Adobe AIR project (which'll run on desktop), it'll ask for image locations on the local pc.
After the user is done selecting images. I want to output a SWF video (slideshow) of the selected images.
How to do the second step. Please guide. I want to create an output file (SWF) from my AIR Flex Desktop Application.
Check out https://github.com/claus/as3swf to compile SWFs at runtime...
This individual seems to have had a similar issue AS3 to Generate Dynamic SWF?
You can try following options from SWFtools
JPEG2SWF Takes one or more JPEG pictures and generates a SWF slideshow from them. Supports motion estimation compression (h.263) for better compression of video sequences.
PNG2SWF Like JPEG2SWF, only for PNGs.
GIF2SWF Converts GIFs to SWF. Also able to handle animated gifs.
Here is what I did :
Install the as3 compiler (mxmlc)
Run the command mxmlc.exe sample.as3 using NativeProcess
import android.media.MediaScannerConnection;
import android.media.MediaScannerConnection.MediaScannerConnectionClient;
These are classes available in Java to refresh the detected images on an SD card on an Android device.
If you save an image to the SD card, it's there, but not visible unless you mount the device, unmount the device. These Java classes fix that problem.
But I'm building an App using AS3 and AIR, does anyone know the equivalent classes for AIR, AS3?
You can use Adobe Air's File class to poke around the device (also cf., Working with Files). Once you figure out what code gets you to the USB device, you can load it as a ByteArray and convert that to an image.
If you are looking for image import/conversion code, just search for what you need; there are numerous posts out there, and the answers are fairly standardized.