Difference between revisions of "Mac Recording and Streaming/ScreenFlow"

From SDA Knowledge Base

Jump to: navigation, search
(ProRes information and some cleanup.)
(Added note about disabling gamma correction.)
Line 53: Line 53:
 
*Click edit and change compression to ProRes 422 HQ.
 
*Click edit and change compression to ProRes 422 HQ.
 
*Change FPS from Current to 60.  Even if your source video is 60 FPS, leaving it at Current will export a 30 FPS video.
 
*Change FPS from Current to 60.  Even if your source video is 60 FPS, leaving it at Current will export a 30 FPS video.
 +
*Turn off automatic gamma correction.
 
*Set audio to Linear PCM.  Sampling rate should be 48 kHz and quality should be at best.
 
*Set audio to Linear PCM.  Sampling rate should be 48 kHz and quality should be at best.
  

Revision as of 09:07, 29 October 2014

Main Website

telestream.net/screenflow/overview.htm


Usage

ScreenFlow does not capture specific regions of your screen when recording (you can select regions after recording). It records the entire screen, but is highly CPU efficient due to its focus on actively changing frames. Here is the basic flow:


  • Go to Preferences -> Advanced and choose adaptive or lossless screen recording (more on this below).
  • Choose whether or not to include your webcam in the recording.
  • Select an audio device or record computer audio.
  • Begin recording.
  • End recording, which brings up the post-production interface.
  • Crop to your desired resolution, and if you want you can add text, transitions, annotations, etc.
  • Select an encoding preset (or create a custom one).
  • Click export and choose a file name.


Screen recordings are 60 FPS by default. Playback in the canvas isn't perfect, so it might look like frames were dropped in the recording even though they really weren't. Assuming your hardware doesn't have performance issues, the encoded videos will show all the frames recorded correctly.


Adaptive VS. Lossless

The adaptive capture method will optimize recording performance by focusing more on movement (changing pixels) and less on still parts of the screen. For instance, if you record a game window ScreenFlow will focus on that rather than the bits of your desktop. The quality is practically indistinguishable from lossless, so use this unless you have a really powerful computer.


Lossless is exactly what it sounds like. Everything on your display is recorded in full for every frame. This method is very taxing at high resolutions, so you may want to do recording tests first to ensure your computer can handle it. To minimize the performance hit, scale your monitor's resolution before recording.


Note: There is a caveat with adaptive. Depending on the visuals and movement in your source, it might mistake certain moments as "still images" and cause dropped frames in an attempt to reduce the file size. This is uncommon, but if it happens use lossless and scale the monitor resolution. You'll still need a reasonably modern computer in order to handle this without dropped frames.


Encoding

There are a number of presets to choose from, but it is recommended that you create custom presets based on the content you record. To do this, go to File -> Export (or press ⌘E) and click Manage. Click the "Copy" button next to a preset (Uncompressed is recommended) and it will appear on the bottom. From here you can edit your encoding settings such as frame rate, bit rate, etc. You can also do this in the main export prompt by selecting a preset and clicking "Customize." The changes made in this manner are temporary and won't be saved to the preset.


Note: ScreenFlow uses x264 but still calls it H.264.


By default the video scale will be your crop settings in the canvas, but you can change it by choosing other scale options from the dropdown or use your own custom resolution.


ProRes Export

ScreenFlow's x264 codec, unfortunately, does tamper with the color space. Exporting videos like this will not preserve accurate colors in your video. For that reason it is highly recommended that you export ProRes, however we won't be using the default preset for it.


  • Click on "Manage" in the export window and copy any preset.
  • Click edit and change compression to ProRes 422 HQ.
  • Change FPS from Current to 60. Even if your source video is 60 FPS, leaving it at Current will export a 30 FPS video.
  • Turn off automatic gamma correction.
  • Set audio to Linear PCM. Sampling rate should be 48 kHz and quality should be at best.


This is a lossy format that retains an extremely high bit rate, making it ideal for offline workflows. It will produce a .mov file. It is highly recommended that you compress it with FFmpeg's x264 codec, as this one will preserve the correct colors as well as allow you the option for CRF or 2-pass encoding.


Warning: ScreenFlow takes a while to export a file like this, much longer than the progress bar would suggest. If your output file is 32 GB, then you'll actually need 64 GB of free space (temporarily). The finished export will still be 32 GB and the extra space is restored. For long videos it may look like ScreenFlow won't finish, but rest assured that it will.


Lossless Export

This is an alternative to ProRes. In nearly all cases it's not worth choosing this, but it is an option if you want absolutely no compression. To use it, follow the steps above for ProRes, but for the codec choose Uncompressed 10-bit 4:2:2.


If you force quit ScreenFlow during the export process it won't delete the temp file, resulting in storage space being held hostage. You can find these temp files here:


  • /private/var/folders/6b/q33l69c55dbcd07m0bjw82f00000gn/T/net.telestream.screenflow4.legacyexporter/TemporaryItems
Personal tools