I am using GPUImage library to compress a video in my iOs app (GPUimageVideoCamera)
https://github.com/BradLarson/GPUImage/
I have worked with it on iOS and it is very fast
I want to do the same in my android app, but it seems that GPUImageMovie class doesn't exist in android library:
https://github.com/CyberAgent/android-gpuimage/tree/master/library/src/jp/co/cyberagent/android/gpuimage
It seems that android library only work on images (no video).
Anyone know if this library can do the job? If not, did someone developed GPUImage all library? If not, what is the best library i can use that can do the job as fast as GPUImage library do.
That's what GPUimageVideoCamera do in iOs (Filtering live video):
To filter live video from an iOS device's camera, you can use code like the following:
GPUImageVideoCamera *videoCamera = [[GPUImageVideoCamera alloc] initWithSessionPreset:AVCaptureSessionPreset640x480 cameraPosition:AVCaptureDevicePositionBack];
videoCamera.outputImageOrientation = UIInterfaceOrientationPortrait;
GPUImageFilter *customFilter = [[GPUImageFilter alloc] initWithFragmentShaderFromFile:#"CustomShader"];
GPUImageView *filteredVideoView = [[GPUImageView alloc] initWithFrame:CGRectMake(0.0, 0.0, viewWidth, viewHeight)];
// Add the view somewhere so it's visible
[videoCamera addTarget:customFilter];
[customFilter addTarget:filteredVideoView];
[videoCamera startCameraCapture];
This sets up a video source coming from the iOS device's back-facing camera, using a preset that tries to capture at 640x480. This video is captured with the interface being in portrait mode, where the landscape-left-mounted camera needs to have its video frames rotated before display. A custom filter, using code from the file CustomShader.fsh, is then set as the target for the video frames from the camera. These filtered video frames are finally displayed onscreen with the help of a UIView subclass that can present the filtered OpenGL ES texture that results from this pipeline.
The fill mode of the GPUImageView can be altered by setting its fillMode property, so that if the aspect ratio of the source video is different from that of the view, the video will either be stretched, centered with black bars, or zoomed to fill.
For blending filters and others that take in more than one image, you can create multiple outputs and add a single filter as a target for both of these outputs. The order with which the outputs are added as targets will affect the order in which the input images are blended or otherwise processed.
Also, if you wish to enable microphone audio capture for recording to a movie, you'll need to set the audioEncodingTarget of the camera to be your movie writer, like for the following:
videoCamera.audioEncodingTarget = movieWriter;
Is there a library that can do the same in android?
Related
There are 2 ways (that I'm aware of) to capture images/videos from the camera in an ionic app:
Native camera app
'Camera Preview' library
The first option I know will allow users to maximise the potential of the camera (quality, megapixels etc.), but I need the flexibility of adding an overlay (basically I need the flexibility of the second option).
Question
In the docs I can only see the ability to see a 'quality' argument as part of the 'takePicture' call, how would a maximum of 100 here compare to the quality of a pic I'd have got from the native app?
I know this is called 'camera preview' but ideally I need it to be the best image quality the camera's capable of capturing (same as the native app).
https://github.com/cordova-plugin-camera-preview/cordova-plugin-camera-preview
Take snapshot of the camera preview. The resulting image will be the same size as specified in startCamera options. The argument quality defaults to 85 and specifies the quality/compression value: 0=max compression, 100=max quality.
CameraPreview.takePicture({width:640, height:640, quality: 100}, function(base64PictureData|filePath) {
// One simple example is if you are going to use it inside an HTML img src attribute then you would do the following:
imageSrcData = 'data:image/jpeg;base64,' + base64PictureData;
console.log(imageSrcData);
});
For More Info Check Documentations.
I'm using the Sony Camera API for taking a picture remotely, but when I rotate the camera streaming image is still vertical. API ver. is 2.40. I checked the Reference of API but there is nothing about orientation of live view
Look to api getevent (pooling or callback) , you will see a liveviewOrientation value in the result.
{
"type":"liveviewOrientation",
"liveviewOrientation":"90"
}
Then you have to rotate your output stream.
It's device dependant
Rotate:
Read the stream, look for Common Header to decode "Packet",then extract JPEG image from one "Packet",decode it.
Rotate the image according to liveviewOrientation, then show it to your display.
I have used JavaCv (and opencv too) to implement live face detection preview on Android. I work ok. Now I want to take a picture or record a video from live preview which have face detection (I mean when I take a picture, this picture will have a person and a rectangle around his/her face). I have researched a lot but get no result. Can anyone help me please !!!
What you're looking for is the imwrite() method.
Since your question isn't clear on the use-case, I'll give a generic algorithm, as shown:
imwrite writes a specified Mat object to a file and it accepts 2 arguments - fileName and Mat object, for example - imwrite('output.jpg',img);
Here's the logic you can follow:
Receive input frame (Mat input from video and run face detection using your existing method.
Draw a rectangle on an output image (Mat output).
Use imwrite as - imwrite('face.jpg',output)
In case you want to record all the frames with a face in them, replace 'face.jpg' with a string variable that is updated with each loop iteration and run imwrite in a loop
If you wish to record a video. Have a look at VideoWriter() class
Is there a known API or way to SCAN the text from a card without actually manually saving (and uploading) the picture? (iOS and Android)
Then I would need to know if that API can determine the marquee within the camera that should be scanned.
I want a behaviour similar to the one of QR scanners, or Augmented Reality apps. Where the user just directs the camera and the action occurs.
I have printed cards with a Redeem code in Text, and including QR will need to change the current card production.
The text is inside a white box, which may make it easier to recognise:
On iOS, you would use CIDetector with an AVCaptureSession. It can be used to process capture session output buffers as they come in from the camera without having to take a picture and provide text scanning.
For text detection, using CIDetector with CIDetectorTypeText will return areas that are likely to have text in them, but you would have to perform additional processing for Optical Character Recognition.
You could also use OpenCV for a not out of the box solution.
You can try this: https://github.com/gali8/Tesseract-OCR-iOS
Usage:
// Specify the image Tesseract should recognize on
tesseract.image = [[UIImage imageNamed:#"image_sample.jpg"] g8_blackAndWhite];
// Optional: Limit the area of the image Tesseract should recognize on to a rectangle
tesseract.rect = CGRectMake(20, 20, 100, 100);
// Optional: Limit recognition time with a few seconds
tesseract.maximumRecognitionTime = 2.0;
// Start the recognition
[tesseract recognize];
I am trying to grab consecutive frames from android using opencv VideoCapture class. Actually I want to implement optical flow on android for which i need 2 frames. I implemented optical flow in C first where I grabbed the frames using using cvQueryFrame and every thing work fine. But in android when I call
if(capture.grab())
{
if(capture.retrieve(mRgba))
Log.i(TAG, "first frame retrived");
}
if(capture.grab())
{
if(capture.retrieve(mRgba2))
Log.i(TAG, "2nd frame retrived");
}
and then subtract the matrices using Imgproc.subtract(mRgba,mRgba2,output) and then display the output it give me black image indicating that mRgba and mRgba2 are image frames with same data. Can any one help how to grab two different images. According to opencv documentation mRgba and mRgba2 should be different.
This question is an exact duplicate of
read successive frames OpenCV using cvQueryframe
You have to copy the image to another memory block, because the capture always returns the same pointer.