video-processing

问题 I have an oddly difficult task to perform. I thought it would be easy, but all my efforts have been fruitless. I'm converting videos uploaded to a php script from various formats (.avi, .mpg, .wmv, .mov, etc.) to a single .flv format. The conversion is working great but what I'm having trouble with is the resolution of the videos. This is the command I'm currently running (with PHP vars): ffmpeg -i $original -ab 96k -b 700k -ar 44100 -s 640x480 -acodec mp3 $converted Both $original and

问题 I am trying to study how to use Kalman filter in tracking an object (ball) moving in a video sequence by myself so please explain it to me as I am a child. By some algorithms (color analysis, optical flow...), I am able to get a binary image of each video frame in which there is the tracking object ( white pixels) and background (black pixels) -> I know the object size, object centroid, object position -> Just simple draw a bounding box around the object --> Finish. Why do I need to use

问题 In my Windows 8 Store Application, I tend to perform live video stream processing (Face detection for example). Technique 1 In my previous Windows 7 application, I was able to use the following technique (Camera Face Detection in C# Using Emgu CV (OpenCV in .NET) and WPF) to perform live video processing. The technique was, having a fixed period timer callback, to actively query image buffer from camera object . void timer_Tick(object sender, EventArgs e) { Image<Bgr,Byte> currentFrame =

问题 I'm looking for efficient way to reduce some video weight (as a File , for upload) and obvious answer for that is: lets reduce resolution! (fullHD or 4K not needed, simple HD is sufficient for me) I've tried lot of ways which should work through lot of APIs (needed 10) and best way was using android-ffmpeg-java, BUT... on my pretty fast almost-current flagship device whole process lasts about length_of_video*4 seconds and also this lib weight is 9 Mb, this amount increases my app size... No

问题 Closed. This question is off-topic. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 5 years ago . I am trying to write a c# code to extract each frame of a .avi file and save it into a provided directory. Do you know any suitable library to use for such purpose? Note: The final release must work on all systems regardless of installed codec, or system architecture. It must not require the presence of another

问题 I'm looking to implement a function that retrieves a single frame from an input video, so I can use it as a thumbnail. Something along these lines should work: // filename examples: "test.avi", "test.dvr-ms" // position is from 0 to 100 percent (0.0 to 1.0) // returns a bitmap byte[] GetVideoThumbnail(string filename, float position) { } Does anyone know how to do this in .Net 3.0? The correct solution will be the "best" implementation of this function. Bonus points for avoiding selection of

问题 I've browsed the internet for this very intensively, but I didn't find what I needed, only variations of it which are not quite the thing I want to use. I've got several videos in different lengths and I want to extract 20 images out of every video from start to the end, to show the broadest impression of the video. So one video is 16m 47s long => 1007s in total => I have to make one snapshot of the video every 50 seconds. So I figured using the -r switch of ffmpeg with the value of 0

问题 I am developing media server for Play station 3 in iPhone. I came to know that PS3 doesn't support .MOV file so I have to convert it into Mp4 or something other transcode which PS3 support. This is what I have done but it crashes if I set different file type than its source files. AVURLAsset *avAsset = [AVURLAsset URLAssetWithURL:videoURL options:nil]; NSArray *compatiblePresets = [AVAssetExportSession exportPresetsCompatibleWithAsset:avAsset]; if ([compatiblePresets containsObject

问题 Is it possible to run ffmpeg from the command line which will either place the 'moov atom' metadata in the beginning of the MP4 file or run the qt-faststart as a post processing operation in ffmpeg so the generated file is stream-able through the internet? I can of course run it as a separate command, but would prefer it to be something as an option within ffmpeg, or as part of a post conversion, command line option when converting the video files via ffmpeg Edit 1 http://ffmpeg.org/ffmpeg

问题 I am trying to implement a hybrid video coding framework which is used in the H.264/MPEG-4 video standard for which I need to perform 'Intra-frame Prediction' and 'Inter Prediction' (which in other words is motion estimation) of a set of 30 frames for video processing in Matlab. I am working with Mother-daughter frames. Please note that this post is very similar to my previously asked question but this one is solely based on Matlab computation. Edit: I am trying to implement the framework