Overlays allow a graphic or effect to be placed on top of the video. They have no effect on audio.
Overlays can be added to any input or mixer. This is defined when creating or updating the overlay, by setting the source
to e.g. input1
or mixer2
. Multiple overlays can be added to each input or mixer.
Overlays can be created, updated, and deleted using the API. They can also be created at start-up using a config file.
All types of overlays have the following properties:
Name | Can be set initially? | Can be updated?? | Description | Default value (if not set) |
---|---|---|---|---|
id |
No | No | ID of the overlay. Positive integer. Starts at 1 and increases by 1 for each new overlay. | n/a |
uid |
No | No | Unqiue ID - a string in the format 'overlayX' where X is the ID | n/a |
type |
Yes | No | The name of the overlay type, e.g. text . |
N/A - REQUIRED |
visible |
Yes | Yes | Boolean. Whether the effect is visible on the video. | False |
source |
Yes | Yes (but only in the NULL or READY states) | The uid of the input or mixer that the overlay is overlaying. e.g. mixer1 |
The mixer with the lowest ID (usually mixer1 ) |
Brave currently supports these overlay types:
Shows text on the screen.
In addition to the common properties defined above, this overlay also has:
Name | Can be set initially? | Can be updated?? | Description | Default value (if not set) |
---|---|---|---|---|
text |
Yes | Yes | The text to display. | Empty string |
valignment |
Yes | Yes | The vertical alignment of the text. Can be top , center or bottom . |
Empty string |
The clock
overlay shows the current time, and also any other text provided in the text
property. It is a useful overlay to determine if there is any delay in the video.
This overlay shares the same properties as the text
overlay.
The effect
overlay allows a range of video transformation effects to be applied.
This overlay has one additional property - effect_name
- which can be set to one of the following values:
agingtv
: AgingTV (adds age to video input using scratches and dust)burn
: Burn (adjusts the colors in the video)chromium
: Chromium (breaks the colors of the video)dicetv
: DiceTV ('Dices' the screen up into many small squares)dilate
: Dilate (copies the brightest pixel around)dodge
: Dodge (saturates the colors in the video)edgetv
: EdgeTV effectexclusion
: Exclusion (exclodes the colors in the video)optv
: OpTV (Optical art meets real-time video)radioactv
: RadioacTV (motion-enlightment)revtv
: RevTV (A video waveform monitor for each line of video)rippletv
: RippleTV (ripple mark effect on the video)solarize
: Solarize (tunable inverse in the video)streaktv
: StreakTV (makes after images of moving objects)vertigotv
: VertigoTV (blending effector with rotating and scaling)warptv
: WarpTV (goo'ing of the video)
If omitted, the default is edgetv
.