Pointers to record audio and video

Today media plays major life in various segments of people. People access media also on multiple devices, PC, mobile and tablet. It serves as good tool by start-ups to explain their products and by marketers to demonstrate the value of the product and job seekers to project their profiles. if you are a teacher or presenter, you also need to understand media. Can all these segments of people create the right set of media for all devices.

Typically, a teacher might work with a third party to provide audio and video services. He requests for delivery of the media assets on a hard drive. The teacher needs to ask the service provider whether he can deliver a compression version which you might be able to use right away in e-learning or m-learning. The teacher needs to demand for the highest quality version in its original format. The less changes and re-encoding of a video, the better the end quality will be and provides a greater amount of flexibility to re-compress or edit the content in the future. Each re-encoding may degrade the quality of your video.

When the teacher does self recording with own equipment, it is better to output a hi-res final version or archive your original assets for access in the future. It might also be a good idea to have the highest quality possible for both video and audio assets to deliver on the web and compress the file to a small file size so that your learners can easily access the content from home, work, or mobile devices.
We recommend that, whenever possible, you always supply a video in its original format.

Developers often forget to compress audio when prepping it for the Web, which leads to slower load times and an unnecessary increase in bandwidth.

    There are two main factors to consider while compressing video .

  • Frame rate: Video is typically 29.97 frames per second (fps) when pulling it from digital devices. When we compress the content for playback on the Web, we try to reduce it to 10-15 frames per second. This makes the file size smaller because you are using fewer frames. You can easily do this on most compression software with a click of a button. when compressing, try to avoid a ripping effect on playback.
  • Codec: A codec is the compression format you choose for playback of your content. The most common format today is H264, which you can use within Flash or HTML5. The compression codec you choose will compress each frame of the video and allow for smaller file sizes, which means quicker downloads or viewing.
  • Bit-rate: As bit-rate is highly dependent on codec, there is no recommended or minimum value. Videos should be optimized for resolution, aspect ratio and frame rate rather than bit rate.
    Whether you are outputting audio for use in podcasts, or to import into PowerPoint, you can optimize your audio by considering the below factors.

  • Select a Codec: You can also compress audio using one of several codecs. The most common formats are MP3 or no audio compression. If you are using Flash, then you want to use the MP3 format to keep the audio files small and make it easier for your audience to hear the content as quickly as possible.
  • Stereo vs mono: Usually when you record audio, the default is stereo, but you want to convert to mono for most productions. This will reduce your file size by half, which again allows for faster downloads and smaller memory requirements.
  • Frequency kHz: When you import audio, the resulting sample rate is 44.1 kHz. However, for most audio productions you want to select 22.050 kHz. This also cuts the file size in half and makes it easier for your production to work with multiple files while maintaining the smallest file size. One rule of thumb is to use a 16 kbps bit rate for audio playback and a bit rate of 64 kbps for voice recordings
  • Aspect Ratio: You need to know the aspect ratio of primary target player or the device where video plays to decide the aspect ratio for the device. For example, to support a video player with aspect ratio (ratio of the width to the height) of 4:3, videos should be created with an aspect ratio of 4:3 to ensure the best quality when played back.

If you have audio or video editing software, get the audio or video is one of the above formats. Also be prepared with some mechanism to organize the media, when working with multiple files per day or week.

Some generic pointers

  • Videos do not start playing right away. A small amount of the video needs to download before the player begins to display the video. This pause depends on the viewer’s internet connection.
  • Video files some times are large for the internet connection to handle and this makes the video could look ‘choppy’. One can lower the bitrate of the video by lowering the quality or compression settings when the video is created.
  • The maximum size for an audio or video file is 200 MB for web platform, but we recommend that files be kept as small as possible to insure optimum playback results. This would be too huge a size for feature phones.