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• How to process video stream ?

  27 avril 2016, par sharpener

  I would like to ask some experienced multimedia professional how to proceed with following task :

  Given URL provides video stream and we would like to get access to decoded frames (byte stream in memory) in managed Win7+ application (C#). We don’t want to render/present the frames the standard way. The video format is known but not fixed (might get changed between two successive sessions, but we will know the parameters).

  So far, I have found there are several methods and I have build following picture in my mind :

  1. ffmpeg wrapper
     • Pros
       1. Self contained (no dependency to windows technologies)
       2. Powerful
     • Cons
       1. Little more complex to understand
       2. Lot of different wrapping variants (FFmpeg.NET, ffmpeg-sharp, ffmpeg-shard, FFmpeg.AutoGen, ...)
  2. DirectShow wrapper
     • Pros
       1. Widely used/supported technology (variaous filters freely available)
       2. Nice/detailed documentation on MSDN
     • Cons
       1. Quite old
       2. Considered obsolete from the point of author’s view (available only for desktop model on runtime >= Win8)
  3. MediaFoundation wrapper
     • Pros
       1. Theoretical successor of DirectShow, so should be available in the future
     • Cons
       1. Seems to be not as good as DirectShow
       2. Not very popular, limited "community" support
  4. FFmpegInterop wrapper
     • Pros
       1. Microsoft’s open source wrapper alternative
     • Cons
       1. Not available for runtime < Win8

• swscale/aarch64/yuv2rgb : add neon yuv42{0,2}p -> gbrp unscaled colorspace converters

  6 août 2024, par Ramiro Polla

  swscale/aarch64/yuv2rgb : add neon yuv420,2p -> gbrp unscaled colorspace converters
  checkasm —bench on a Raspberry Pi 5 Model B Rev 1.0 :
  
  yuv420p_gbrp_128_c : 1243.0
  
  yuv420p_gbrp_128_neon : 453.5
  
  yuv420p_gbrp_1920_c : 18165.5
  
  yuv420p_gbrp_1920_neon : 6700.0
  
  yuv422p_gbrp_128_c : 1463.5
  
  yuv422p_gbrp_128_neon : 471.5
  
  yuv422p_gbrp_1920_c : 21343.7
  
  yuv422p_gbrp_1920_neon : 6743.5
  

  • [DH] libswscale/aarch64/swscale_unscaled.c
  • [DH] libswscale/aarch64/yuv2rgb_neon.S

• Way to bypass video upload when testing using Rspec

  1er mars 2014, par Justin

  I'm testing a page on my app that shows videos. I'm trying to speed up the test by bypassing the video upload process or another way ??

  Maybe I'm using FactoryGirl incorrectly for file uploads..

  Using FactoryGirl, I'm creating the video with

  FactoryGirl.define do
  
   factory :video do
  
    user_id 1
  
    type "Live"
  
    title "FooBar"
  
    description "Foo bar is the description"
  
    video { fixture_file_upload(Rails.root.join('spec', 'files', 'concert.mov'), 'video/mp4') }
  
   end
  
  end

  And in the request's spec I'm describing the videos as :

  describe "videos page" do
  
  
  
    let(:user) { FactoryGirl.create(:user) }
  
    let!(:video1) { FactoryGirl.create(:video) }
  
  
  
    before { visit user_video_path(user) }
  
  
  
    it { should have_title(user.name) }
  
    it { should have_content(user.name) }
  
  
  
    describe "videos" do
  
      it { should have_content(video1.description) }
  
    end
  
  end

  Now, everytime I run the test for this page it goes through the file upload process which takes more time. I'm also using FFmpeg

  **video.rb (video model)**
  
  
  
  validates :video, presence: true
  
  has_attached_file :video, :styles => {
  
                                        :medium => { :geometry => "640x480", :format => 'mp4' },
  
                                        :thumb => { :geometry => "470x290#", :format => 'jpg', :time => 10 }
  
                                       }, 
  
                            :processors => [:ffmpeg]

  What this does when I test the page is the CLI goes through the video upload process like it would if you were uploading the video and watching your local server.