fgrab -- User's Guide



Three different capture modes:


- Economy mode

This is the preferred mode. The screen action is directly recorded as .fvf movie file, which can be played back immediately after the recording session. fgrab only captures the area of the screen that is in motion. No screen action implies no CPU load / no data written. Nevertheless, fgrab writes a full frame every 4 seconds to increase the editability of fvf clips in FastCut. One can check the required CPU usage with the 'Activity Monitor'.


- Game mode (or fullscreen mode)

Every 1/fps second the full frame (C frame) will be captured. That means higher CPU load and a larger quantity of data written to disk. This mode is appropriate for games for instance when economy mode does not work or in some other cases.


- H.264 mode

The screen action is directly recorded as H.264 movie file (.mov).


[the CPU load in comparison to each other: economy mode 0%-45%; full screen mode 45%; H.264 mode 15% (referred to the CPU usage of one core of a MacBook Pro 15'' late 2013)]



Advices and hints / Q & A:


- When you hit the 'Save' button, the screen movie is saved on the desktop (a .fvf or .mov file is created). If you hold down the shift key while you hit the 'Save' button, a save as panel is shown that allows you to choose whatever save path you want. If you have an App Store version of fgrab, at first specify a save location folder, files won't be saved by default on the desktop. Notice that the App Store version differs from the regular version since it is restricted by App Sandbox.


- Important Question: I have double-clicked a recording file (.fvf), how can I move the playhead in the player window? -- Hold down the command key and press the 'jump to previous/next keyframe‘ button.


- How to use another volume as scratch disk? Easily move the fgrab.app file to the desired volume. During capturing the data is temporarily saved inside fgrab's application bundle. Note that flash storage might be faster than a hard disk. [This technique does not work if you have your fgrab version from the Mac App Store (MAS)!]


- Why is mac system audio mute during recording? When you capture mac audio and the microphone input, without setting the output volume to zero backcoupling would be the result.


- Retina display settings: to benefit from your high-res retina display, check the '2x retina display mode' option in FastCut's preferences. Retina display modes are not detected automatically. Only 2x mode is recommended and supported. The retina setting is taken over to fgrab and fvf_player. [If you have got a MAS fgrab version, then the FastCut setting is not taken over, in this case the system's monitor settings are respected.]

Notice, if you have enabled retina mode in FastCut's preferences, fgrab will use approx. 100 megabytes of memory (measured on a MacBook Pro 15'' with a screen size of 2880 x 1800), otherwise about 50 megabytes.


- Please note that you must set in and out points before you insert/add .fvf screen movies to FastCut projects.


- How do I insert .fvf screen movies to a FastCut project? -- Select a video track and move the playhead slider to a position where you want to insert the .fvf clip. Then choose 'Insert Screen Movie ...' from the 'Movie' menu and specify the .fvf file. Hold down the shift key whereas you select the menu command to modify the insert command to an add command. You can download the FastCut video editor from <http://www.timesforfun.de/download/FastCut.zip>


- Remove/uninstall your old application versions! Otherwise undesired conflicts may occur.


- fgrab was rewritten for OS X 10.10 Yosemite (fgrab now requires at least Mac OS X v10.10 or later). A legacy version which runs on Snow Leopard is available, too. To unlock fgrab, choose 'Register fgrab ...' from the 'fgrab' application menu and enter name and serial number. If you have a MAS fgrab version, registration is handled by Apple.


- If you would like to record the mac system audio in addition to the screen action, you have to additionally download/install the required 'Soundflower' kernel extension. Once it is installed a checkbox will appear in the main window (after having re-launched fgrab) which allows you to optionally record the Mac system audio. You can download 'Soundflower' directly from <https://github.com/mattingalls/Soundflower/releases/download/2.0b2/Soundflower-2.0b2.dmg>.


- fgrab is slow, it doesn't reach 30 fps even though I have configured it... -- You should have at least 8 GB of free space on your startup hard disk drive. But there are also other causes worth considering.


- Since v1.5.1 fgrab has a scale option. This yields smaller files and less CPU usage.


- Everytime I put a fvf clip in the FastCut 'Timeline' it appears pixelated and very poor quality. -- Make sure that you set the 'movie size' in the 'preferences' dialog to the size of your fvf clip (=screen size). The actual output export size may be set later in the QuickTime export dialog. Also make sure that the framerate in the 'preferences' dialog is set to the framerate of your fvf clip(s) or higher. Don't decrease the framerate later in the QT export dialog; this would result in artefacts. If you want a framerate of 15 fps for instance, then capture the screen with 15 fps at the outset.


- You can play back a .fvf recording with the fvf_player. For this purpose double-click the file in the Finder or double-click the already inserted fvf clip in FastCut. You can make your in and out point changes go back to FastCut and the timeline automatically reflects the changes.


- How to get the associated audio comment of a .fvf file into the FastCut 'Timeline'? -- When you have already inserted the .fvf clip into the timeline ('Movie' > 'Insert Screen Movie') it is easy. Just drag and drop the fvf clip from one of your video tracks into a audio track while holding down the command key to perfrom a 'drag copy' operation. When the fvf clip is dropped on A1, an audio clip of the captured mac audio (if it exists) will be created. Else an audio clip of the voice-over (if it exists) will be created.


- Use the 'Set In Point'/'Set Out Point' buttons to set the in/out points. To jump to the in/out points hold down the shift key while pressing these buttons.


- The 'jump to key' button in the fvf_player (hover over the buttons/controls in the fvf_player window to obtain an explanation of their function) moves the playhead to the next K frame. If you hold down the command key the pressing the button moves it to the next C frame. What's that? A K frame is a full frame created with the 'make key' button in fvf_player. A C frame is a full frame generated by fgrab.


- A segment in fvf_player is defined by an in point and an out point. You can manage several of them, not only one. With the plus and minus buttons you can add and delete segments; with the popup menu you can select the active segment.


- I bought fgrab in the Mac App Store (v1.5.2 is the first release also sold in the MAS), how differs this fgrab version I got there from the normal version? -- The fgrab application distributed over the MAS is self-contained, everything is packed in one app bundle file which will be installed in your /Applications folder. The fvf_player (required) companion app must be downloaded separately in the MAS (for free); it allows you to play back your recorded screen movies and set in/out points among other things.


- The first time when you hit the 'Save' button (assuming you own the App Store version), please choose the default save location for your recording files. We recommend to choose the ~/Desktop folder. You can change this output folder at any time by selecting 'Choose Save Location ƒ ...' from the 'fgrab' menu. Whenever you hit the 'Save' button this is the folder where your recording files will be saved.


- You can obtain more products from the developer who has written this piece of software online, please visit <http://www.timesforfun.de/>