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No Sound in Windows? How to Fix It (Output Device, Drivers and Audio Service)
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When recording with oCam, the following error message may appear after a certain amount of time:
"Error while writing video frame (error=-28)"
This error (error code 28) occurs when the file system of the path where the recorded video file is being saved is formatted as FAT (FAT32). The FAT file system has a maximum single-file size limit of 4 GB, so this error occurs when the recorded file size exceeds 4 GB. Below is a detailed explanation of how to resolve this issue.
To fix this error, you can choose one of the following two methods:
1. Change the save path to an NTFS file system
The NTFS file system has a much larger file size limit (up to 16 EB), so it can store video files larger than 4 GB without any problems. To change oCam's save path to a drive or folder that uses the NTFS format, follow these steps:
1. In the oCam main window, click 'Tools' in the top menu, then select 'Options'.
2. In the Settings window, click the 'Save' category in the left menu.
3. Under the 'Save Path' item, check the current path and change it to another drive or folder that uses the NTFS file system (for example, `C:\Videos` or `D:\Recordings`).
4. Click the 'OK' button to save the settings, restart oCam, and then try recording again.
2. Format the existing drive as NTFS
If the drive you are currently using is formatted as FAT or FAT32, you can convert or format it to NTFS. However, formatting will erase all data on the drive, so be sure to back up any important files first. To format the drive, follow these steps:
1. Open File Explorer and right-click the drive you want to format (for example, a USB drive or external hard drive).
2. Select 'Format' and set the file system to 'NTFS'.
3. Choose the formatting options, then click 'Start' to begin formatting.
4. After formatting is complete, set that drive as the save path in oCam and use it.
Additional Checks
- To check whether the drive's file system is FAT32, right-click the drive in File Explorer and select 'Properties' to view the file system information.
- If the problem continues even after changing to NTFS, check whether the drive has enough free space and whether you have write permission.
By changing the save path to an NTFS file system or formatting the drive, you can save large video files over 4 GB without errors. After changing the settings, make a test recording to confirm that the problem has been resolved.
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.