Was this article helpful?

Flash Encoder Presets

Last modified 12:33, 7 Aug 2013

 

Encoder Presets - Flash standard default.jpg

NOTE: The Flash custom settings apply to the following Encoder Presets: Flash, YouTube, Livebeats, iNK Barrel, ShowCaster, Streaming Media Hosting, and Stretch Internet.

 

Video Encoding​

 

Encoder

Choose between H.264 and VP6.

Width / Height

Set the dimensions on your stream.

Frames per second

This program comes preset with frame rates of 8, 10, 12, 15, 24, 25, 29.97, 30, 50, 59.94, and 60 frames per second, but you can also set a custom frame rate.

Average Bit Rate

Set an average bit rate to set an encoding data rate target. A modest bit rate can prevent data spikes which may impair consistency of quality.

Higher numbers provide better quality. The connection speed of your audience is a significant factor in determining your target bit rate. The encoder will compress the video to approximate this target. However, at different times during your broadcast the bit rate may be higher lower than the target rate. The exact value is not guaranteed.

Profile

NOTE: The setting is available when using the H.264 encoder only. It is not available in VP6.

Choose between the Baseline and Main profiles.

The Baseline profile is commonly used in mobile applications. It is also used in other applications which operate with limited processing power, storage capacity, and/or bandwidth.

The Main profile is appropriate for general-purpose applications of broadcast media, such as high-bandwidth Internet broadcasting.

Key frame every ____ frames

Set the frequency of key frames in your GOP structure.

A movie is a sequence of images and each image is called a frame. To compress video data, most encoders take a frame and make it a reference (also known as a key). This keyframe is sent as part of the broadcast, and all of the data after that keyframe is relative to it. The benefit of this is that the compressor only needs to send what has changed since the last keyframe.

The main drawback of this is that over time it becomes harder for the encoder to distinguish the frame-difference information, especially if there is a lot of motion in the video. Another drawback is if your viewer’s computer misses a keyframe, the video will be distorted until the next keyframe is sent. However, you can control how often the encoder makes a new keyframe by setting the number of frames. The more keyframes you broadcast, the more bandwidth required and less compression, but results in better quality video.

Timecode every ____ frames

Check this box to send timecode metadata at regular intervals.

Wirecast can generate timecodes embedded in the Flash stream. If a frames value of zero is entered, the timecode is never sent. Wirecast sends metadata along with the frames. This data looks like an onFI call. Various timecodes and timestamps are also sent with the stream.

 

Audio Encoding

 

H.264 uses AAC audio while VP6 uses MP3 audio.

Channels

Choose Mono or Stereo for your audio stream.

Mono uses less bandwidth than stereo, but stereo is more pleasing to the listener. Wirecast does not support more than two channels of audio.

Target bit rate

This is the target bit rate of your audio. Higher numbers provide better quality. The connection speed of your audience is a significant factor in determining your target bit rate. The encoder will compress the audio to approximate this target. However, at different times during your broadcast the bit rate may be higher lower than the target rate.

The total broadcast bit rate is a function of video bit rate plus audio bit rate.

Sample rate

This value specifies how many thousands of times per second to sample the audio in the broadcast. Higher values provide better quality sound, but at greater bandwidth.

Tags

Comments

You must to post a comment.

Attachments