I've got an old sony handycame that record into tapes.
When i try to display the videos in my samsung tv using RCA cables, the video is full screen and with a really good quality.
I wanted to transfer the videos into my computer using usb communication.
I've got the handycam's driver, installed, the handycam is recognized as well.
Using OpenCV library, have been able to collect the pictures but in a resolution of 320*240.
When i try to resize the pictures, the quality get really bad.
I would like to have videos of more than default resolution, with a good quality.
So, how come that the videos are displayed so well into the tv, but not in my computer ? and is there any way to solve this problem ?
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I'm working on video processing app for the iPhone using OpenCV.
For performance reasons, I wan't to process live video at a relatively low resolution. I'm doing object-detection on each frame in the video. When the objects are found in the low-resolution video frame, I need to acquire that exact same frame at a much higher resolution.
I've been able to semi-accomplish this using a videoDataBufferOutput and a stillImageOutput from AVFoundation, but the still image is not the exact frame that I need.
Are there any good implementations of this or ideas on how to implement it myself?
In AVCaptureSessionPresetPhoto it use small video preview(about 1000x700 for iPhone6) and high resolution photo(about 3000x2000).
So I use modified 'CvPhotoCamera' class to process small preview and take photo of full-size picture. I post this code here: https://stackoverflow.com/a/31478505/1994445
Is there any tips, suggestions, or available plugins for Phonegap that might be available to Capture a video using Phonegap's capture feature, then programmatically compress or reduce the quality of the video such that it can be uploaded to a server?
The video file sizes can become rather large with videos longer than 5 minutes. I would strongly prefer not to have save the video to the iPhone.
Currently it is not possible. You might have a look at this plugin, but up to Cordova 3.5 it is not possible to compress a video, and you can set its duration only on iOS
In iOS, I would like to get frame-by-frame images from a movie file,
I tried it by using AVAssetImageGenerator. But it gets one image per second for a 30fps movie. It should be 30images!
I heard that there is a way to use FFmpeg.
But in newer OSs like iOS7, is there a new API to do this without using external libraries like FFmpeg?
You can also try OpenCV to capture the frames. But the speed will be dependent on the device and processor. Hope for iPhone5 the speed is perfect to capture all the frames. You can have a look at this link if it helps.
When capturing video with phonegap on iOS the file size for a even a 1min capture is ridiculously large. Well, far to large to upload over a 3G connection reliably. I read that there is a native AVCaptureSession object that will allow the bitrate to be altered in order to reduce the file size. Has anyone implemented this in the phonegap video capture or can give me any pointers?
Found the deatils I needed here:
How can I reduce the file size of a video created with UIImagePickerController?
The important line for Phonegap users is in CDVCapture.m:
pickerController.videoQuality = UIImagePickerControllerQualityTypeHigh;
There are several presets that can be used e.g.
UIImagePickerControllerQualityTypeLow
phonegap provide quality argument when to navigate camera set :
quality:50
this is recommended for ios. if u need to reduce mean reduce quality.It have integer value (0-100) use this .....
I have an iphone application that uploads videos to youtube. It uploads the video files without a problem. But there is an issue that the thumbnail preview image is of very low quality.
My question is this, is it possible using the youtube api to set a different preview image?
No. this is not possible with the Standard API.
See this answer for possible ways forward. Youtube API - Set the Thumbnail of video