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• ffmpeg to transcode streaming video and storage

  8 septembre 2011, par icarus74

  Examples of ffmpeg that I've seen so far all seem to accept a file on disk storage as input, to transcode it into another file in disk storage as output. Also i've come accross ffserver which can be used to stream-out video. However, yet to find a good tutorial or example of ffmpeg used to transcode streaming video/audio, constrained by say parameters like running-time or no. of frames or other event, and save the transcoded media on disk.

  Any pointers, tips or hints would really help.

• How do I make a video with a static image background in FFMPEG ?

  21 février 2012, par Tim Scollick

  I have an image. I have a transparent FLV. I want to use the image as a background to the transparent FLV and have it outputted as FLV.

  This command works but the video is one frame long :

  ffmpeg -i background.png -f flv -vcodec flv -b 1500k -vf "movie=test_videos/alpha.flv [logo]; [in][logo] overlay=0:0 [out]" -s 800x464 -y output.flv

  I have tried to use the -t and -vframes parameters to no avail.

  Does anyone have any tips ?

• Availability of WebM (VP8) Video Hardware IP Designs

  10 janvier 2011, par noreply@blogger.com (John Luther)

  Hello from the frigid city of Oulu, in the far north of Finland. Our WebM hardware development team, formerly part of On2 Technologies, is now up-to-speed and working hard on a number of video efforts for WebM.
  

  • VP8 (the video codec used in WebM) hardware decoder IP is available from Google for semiconductor companies who want to support high-quality WebM playback in their chipsets.
  • The Oulu team will release the first VP8 video hardware encoder IP in the first quarter of 2011. We have the IP running in an FPGA environment, and rigorous testing is underway. Once all features have been tested and implemented, the encoder will be launched as well.

  WebM video hardware IPs are implemented and delivered as RTL (VHDL/Verilog) source code, which is a register-level hardware description language for creating digital circuit designs. The code is based on the Hantro brand video IP from On2, which has been successfully deployed by numerous chipset companies around the world. Our designs support VP8 up to 1080p resolution and can run 30 or 60fps, depending on the foundry process and hardware clock frequency.

  The WebM/VP8 hardware decoder implementation has already been licensed to over twenty partners and is proven in silicon. We expect the first commercial chips to integrate our VP8 decoder IP to be available in the first quarter of 2011. For example, Chinese semiconductor maker Rockchip last week demonstrated full WebM hardware playback on their new RK29xx series processor at CES in Las Vegas (video below).
  

  
  Note : To view the video in WebM format, ensure that you’ve enrolled in the YouTube HTML5 trial and are using a WebM-compatible browser. You can also view the video on YouTube.

  Hardware implementations of the VP8 encoder also bring exciting possibilities for WebM in portable devices. Not only can hardware-accelerated devices play high-quality WebM content, but hardware encoding also enables high-resolution, real-time video communications apps on the same devices. For example, when VP8 video encoding is fully off-loaded to a hardware accelerator, you can run 720p or even 1080p video conferencing at full framerate on a portable device with minimal battery use.

  The WebM hardware video IP team will be focusing on further developing the VP8 hardware designs while also helping our semiconductor partners to implement WebM video compression in their chipsets. If you have any questions, please visit our Hardware page.

  Happy New Year to the WebM community !

  Jani Huoponen, Product Manager
  Aki Kuusela, Engineering Manager