Skip to content

Commit

Permalink
Add dropped-frames-rule.md
Browse files Browse the repository at this point in the history
  • Loading branch information
dsilhavy committed Jan 29, 2024
1 parent 245588e commit 67398f4
Show file tree
Hide file tree
Showing 5 changed files with 60 additions and 7 deletions.
2 changes: 1 addition & 1 deletion pages/advanced/abr/abandon-request-rule.md
Expand Up @@ -59,7 +59,7 @@ if (remainingBytesToDownload > totalBytesForOptimalRepresentation) {
player.updateSettings({
streaming: {
abr: {
activeRules: {
rules: {
abandonRequestsRule: {
active: true,
parameters: {
Expand Down
53 changes: 53 additions & 0 deletions pages/advanced/abr/dropped-frames-rule.md
@@ -0,0 +1,53 @@
---
layout: default
title: DroppedFramesRule
parent: Adaptive Bitrate Streaming
grand_parent: Advanced Features
---

# DroppedFramesRule

## Description

While the current throughput and the current buffer level might allow playing the video stream on a high
quality `Representation` the underlying platform might not be able to render the content without dropping frames.
Dropped frames refer to video frames that are not successfully delivered or displayed during playback. This can occur
when the video playback system is unable to keep up with the required frame rate, resulting in skipped frames. Dropped
frames can cause a decrease in video quality and a disruption in smooth playback.

The `DroppedFramesRule` monitors the ratio of dropped frames and total frames and reduces the video quality if the ratio
exceeds the value defined in `droppedFramesPercentageThreshold`:

````js
if (totalFrames > settings.get().streaming.abr.rules.droppedFramesRule.parameters.minimumSampleSize
&& droppedFrames / totalFrames > settings.get().streaming.abr.rules.droppedFramesRule.parameters.droppedFramesPercentageThreshold) {
newRepresentation = representations[i - 1];
}
````

## Configuration Options

| Parameter | Description |
|:-----------------------------------|:------------------------------------------------------------------------------------------------------------------------------------------|
| `minimumSampleSize` | Sum of rendered and dropped frames required for each Representation before the rule kicks in. |
| `droppedFramesPercentageThreshold` | Minimum percentage of dropped frames compared to total frames to trigger a quality downs-switch. Values are defined in the range of 0 - 1 |

## Example

```js
player.updateSettings({
streaming: {
abr: {
rules: {
droppedFramesRule: {
active: true,
parameters: {
minimumSampleSize: 375,
droppedFramesPercentageThreshold: 0.15
}
}
}
}
}
});
```
2 changes: 1 addition & 1 deletion pages/advanced/abr/insufficient-buffer-rule.md
Expand Up @@ -41,7 +41,7 @@ So in this case we can select a maximum bitrate of `11.25 Mbit/s`.
player.updateSettings({
streaming: {
abr: {
activeRules: {
rules: {
insufficientBufferRule: {
active: true,
parameters: {
Expand Down
8 changes: 4 additions & 4 deletions pages/advanced/abr/settings.md
Expand Up @@ -31,7 +31,7 @@ ABR rule (`bolaRule`). The `abr` section in `Settings.js` allows a reconfigurati
player.updateSettings({
streaming: {
abr: {
activeRules: {
rules: {
throughputRule: {
active: true
},
Expand Down Expand Up @@ -64,7 +64,7 @@ can be dynamically enabled and disabled.
```js
player.updateSettings({
abr: {
activeRules: {
rules: {
insufficientBufferRule: {
active: false
},
Expand Down Expand Up @@ -92,7 +92,7 @@ player.updateSettings({
|:-------------------------|:--------------------------------------------------------|
| `insufficientBufferRule` | [InsufficientBufferRule](insufficient-buffer-rule.html) |
| `switchHistoryRule` | tbd |
| `droppedFramesRule` | tbd |
| `droppedFramesRule` | [DroppedFramesRule](dropped-frames-rule.html) |
| `abandonRequestsRule` | [AbandonRequestRule](abandon-request-rule.html) |
| `l2ARule` | [L2ARule](l2a.html) |
| `loLPRule` | [LoL+](lol_plus.html) |
Expand All @@ -108,7 +108,7 @@ use `player.addABRCustomRule()` to add your new rule:
/* don't use dash.js default rules */
player.updateSettings({
abr: {
activeRules: {
rules: {
throughputRule: {
active: false
},
Expand Down
2 changes: 1 addition & 1 deletion pages/advanced/abr/throughput-rule.md
Expand Up @@ -31,7 +31,7 @@ parameters are documented [here](throughput-calculation.html).
player.updateSettings({
streaming: {
abr: {
activeRules: {
rules: {
throughputRule: {
active: true
}
Expand Down

0 comments on commit 67398f4

Please sign in to comment.