How to Record Microphone and System Audio

Using oCam at work or school? A license is required, and it removes all ads, including this window. See the paid version →

Below is a detailed guide on how to record audio and configure the settings in oCam.


Recording System Audio by Default

When you start screen recording with oCam, system audio is recorded automatically by default. This includes all sounds played on your computer, such as video audio, game sound effects, and system notification sounds. This setting is applied immediately without any extra steps, making it very convenient for users who want to record only system audio. For example, when recording gameplay footage or creating software tutorial videos, you can capture only the system audio cleanly.


Recording Microphone Audio as Well

If you want to record microphone audio together with system audio, you only need to adjust the settings slightly in oCam. First, click the "Sound" button on the main screen of oCam. A pop-up window for sound settings will then appear. In this window, a list of available microphone devices is shown, and you can select the microphone you want to use. For example, if you are using an external microphone or a headset microphone, simply select and enable that device. Through this process, both system audio and microphone audio are recorded at the same time, which is very useful when creating lecture videos or recordings that require live narration.


Applying the Audio Recording Settings

Once you select the microphone and complete the settings, oCam immediately applies them. After that, when you start recording, both system audio and microphone audio will be recorded together. This feature is especially effective for situations where both your voice and system sound need to be captured at the same time, such as YouTube content creation, online classes, or game streaming. To make sure the settings have been applied correctly, it is a good idea to run a short test recording and check whether the audio is being recorded properly.


Disabling Audio Recording

Sometimes you may want to capture only the screen video without recording any sound at all. In that case, uncheck the "Record System Audio" option in the sound settings window of oCam, and select "Do Not Record Microphone" in the microphone settings as well. With this configuration, oCam records only the screen video without any sound, which is suitable for tasks where a silent video is needed, such as when you plan to add background music separately later.
 

Another helpful tip

How to Reduce the Size of Recorded Video Files When Recording Games (NVIDIA Codec)

If you are using the NVIDIA NVENC H.264 codec by default, the recorded file size may be very large.


Click the Codec menu in oCam to check whether you are using the NVENC H.264 codec, as shown below.

In the oCam Codec menu, click Hardware Encoder Settings.

The Hardware Encoder Settings window will appear as shown below. You can reduce the size of the recorded video file by changing the options highlighted in the yellow box.

First, let's look at how to reduce the size of the recorded file using variable bitrate.

( Rate Control must be set to 1-PASS VBR. )


The Quantizer value can be set from 1 to 51.

The lower the Quantizer value, the better the video quality, and the higher the Quantizer value, the lower the video quality.

In other words, the recording quality is defined by the range from the minimum Quantizer value to the maximum Quantizer value.


For example, 

If the minimum Quantizer value is 1 and the maximum Quantizer value is 13, the recording quality range is 1 to 13.

If the minimum Quantizer value is 1 and the maximum Quantizer value is 51, the recording quality range is 1 to 51.

If the minimum Quantizer value is 13 and the maximum Quantizer value is 51, the recording quality range is 13 to 51.

In conclusion, to reduce the size of a recorded video file, increasing the minimum and maximum Quantizer values will lower the recording quality and reduce the file size.


You can adjust the Quantizer values depending on your needs, as follows.

If you want to maintain the highest recording quality while lowering the quality at certain points to reduce the size of the recorded video, set the minimum Quantizer value to 1 and set the maximum Quantizer value to a higher number depending on how much you want to reduce the quality.

( Example: Minimum Quantizer: 1, Maximum Quantizer: 30 )


If you want to maintain medium quality while lowering the quality as much as possible at certain points to reduce the size of the recorded video, set the minimum Quantizer to 26 and the maximum Quantizer value to 51.

For reference, the minimum Quantizer value cannot be greater than the maximum Quantizer value.

That is, the minimum Quantizer value <= the maximum Quantizer value.


Caution: If you set both the minimum Quantizer value and the maximum Quantizer value to 1, the recorded video file size will become extremely large, so do not use this setting.

The default values in oCam are a minimum Quantizer value of 1 and a maximum Quantizer value of 13, and we recommend setting them within the following range.

Minimum Quantizer >= 1 and Maximum Quantizer value >= 13


Next is how to reduce the size of the recorded video file using constant bitrate.

Change Rate Control to 1-PASS CBR and then set the average bitrate.



The higher the average bitrate, the better the video quality. The lower the bitrate, the lower the video quality and the smaller the recorded file size.


Finally, there is a method that uses a fixed Quantizer parameter.

Set Rate Control to 1-PASS Fixed Quantizer Parameter.



Unlike VBR, there is no concept of minimum and maximum Quantizer values, and the quality is set using a fixed Quantizer value.