How to Record Losslessly Using x264vfw
Before getting started, you must install the x264 codec in advance. If you do not know how to install it, please refer to the Help section.
Click the Codec menu in oCam, then click the External Codec menu item.
Select Use External Codec, choose the x264vfw codec, and then click the Settings button.
Using the default x264vfw settings as a base, change the parts highlighted in the yellow box in the image below as shown.

The following settings need to be changed.
Preset - Ultrafast ( Set this to improve encoding speed. The file size may become larger, but if you choose other options, significant lag may occur. )
Profile - High 4:4:4 ( The default profile may cause quality loss, so change it to High 4:4:4 for lossless encoding. )
Keep input colorspace - Keeps the color space of the internally received input buffer. ( If you use other options, encoding may fail. )
Rate control - Single pass - lossless - Change this for lossless encoding.
Click the OK button to apply the settings.
When recording 64-bit games, the settings are applied to x264vfw64 for 64-bit, so run x264vfw - Configure x264vfw64 from the Start menu and configure it in the same way as shown above.
If you record with the above settings, the video will be recorded losslessly. One important point is that if you want to play back the lossless video without quality loss, you must change the settings in your video player.
Below is how to check a lossless video using PotPlayer.
Run PotPlayer, then click Preferences ( F5 ).
In the Preferences window,
click Video - Color Space/Attributes on the left, then in the Color Space group box on the right, select Convert manually if possible - Default output color space. ( If you do not configure this, even if the recording is lossless, the screen colors may still be altered during playback. )
Click OK, then play the video recorded losslessly.
At this point, press Ctrl + F1 in PotPlayer. As shown below, the output format of the video codec must be displayed as RGB(32 Bits).
Also, in the playback information under the File Information tab, the following properties must match as shown below.
Format profile : High 4:4:4 Predictive@L3
Color space : RGB
Color range : Full
Matrix coefficients : RGB
Please note that Windows Media Player does not play this properly, and preview thumbnails will not be displayed in Windows Explorer.
Today's News/Tips
The system stutters during recording.
If your system becomes slow during recording or the mouse movement stutters, this is likely related to high system resource usage.
In particular, when trying to record high resolution or high frame rates with oCam, this issue can occur if your PC specifications cannot handle the workload.
To solve this, you can reduce system load by adjusting several settings.
First, after running the oCam program, click the Settings button on the main window.
When the Settings window opens, go to the Encoding tab at the top and check the related options.
In this area, you can adjust the Frames Per Second (FPS) setting. If the default is set to 30, try lowering it gradually.
For example, reduce the FPS step by step to 25, 20, 15, and 10, and check whether stuttering decreases.

It is important to find an FPS value that is optimal for your PC specifications through this process.
Additionally, lowering the recording resolution or closing unnecessary background programs can also help reduce system load.
We recommend making these adjustments to balance system performance and recording quality.