1. Overview

AT&T Video Optimizer is a free, open-source tool for developers and testers that provides recommendations to optimize the network performance of video and applications on mobile devices.

Video Optimizer runs traces on a mobile device, collecting network traffic, battery statistics, a video of the screen, and more. Post collection, the results are analyzed against 43 Best Practices, which helps developers pinpoint performance issues in their network traffic, and provides advice on how to resolve the issues. Adhering to these Best Practices has been shown to dramatically improve app and website performance, all of which lead to higher customer engagement and retention.

Video Optimizer complements standard functional and user-based testing as part of any quality assurance program. Video Optimizer allows for simple integration into existing test automation. We recommend that you execute a set of standardized tests such as AQuA's Testing Criteria while using Video Optimizer to qualify your product for readiness.

Video Optimizer User Guide

2. Best Practices

The following Best Practices documents are reinforced by the Best Practice tests in Video Optimizer, and are organized in the same categories.

File Download: These documents provide recommendations for cache management, reducing duplicate content, and compressing and managing the way you download files and images. Smaller files can be delivered in less time, speeding up the rendering of your application.

Connections: These documents provide recommendations for efficiently managing TCP connections. By optimizing how you use the device's radio, you can speed the delivery of content and reduce the battery consumption of your app.

HTML: These documents provide recommendations for optimizing the handling of external files in your HTML. Optimizing your HTTP connectivity can further reduce your application's battery consumption.

Other: Reducing the usage of device peripherals can further reduce the battery consumption of your app.

Video: Analyses of the video packets sent during the data collection to examine for startup delays, stalls and more.

General Topics: These documents provide background on the LTE and 3G energy models and optimizing your app for mobile devices.

3. System Requirements

Before you download Video Optimizer, make sure you meet the following system requirements for your operating system:

• At least 4GB of RAM, but suggested is 8GB
• Java 17 or above
• Android SDK Level 24 or above including ADB
• FFmpeg

Windows

• Wireshark (Install Npcap addon with Winpcap API-compatible mode)
• VLC media player 3.x.x or higher

Mac

• Homebrew
• For iOS developers, use latest version of Xcode and OS X
• Ifuse
• OSXFuse
• libimobiledevice and ideviceinstaller (for taking iOS traces)
• Wireshark
• VLC media player- 3.x.x or higher

Linux

• Wireshark
• For Ubuntu 18.04.x LTS (and newer) users, use VLC media player version 3.x.x
• For Ubuntu 16.04.x LTS (and older) users, use VLC media player version 3.x.x up to 3.0.8

4. Installation

5. Using Video Optimizer for Data Analysis

Video Optimizer takes the trace data collected from your app, evaluates it against the Video Optimizer Best Practices tests, and presents the results in the form of diagnostics and statistics that provide a layered view into the performance of your app. The quickest way to get started with Video Optimizer is to download a sample trace, open it in the Data Analyzer, and review the Video Optimizer Best Practice test results.

Starting the Analysis

As soon as you open a trace file in Video Optimizer, it will begin its trace analysis by evaluating the data against a set of recommended best practices. Once the analysis is complete, the Video Optimizer will automatically display the results.

Reviewing Video Optimizer Results

The best place to start reviewing Video Optimizer’s test results is in Video Optimizer’s Best Practices / Results tab. This tab contains a high-level overview of the results. When Video Optimizer runs an analysis of your trace, it evaluates the trace, it evaluates the trace data against a set of Best Practices benchmarks for over 20 distinct tests. If your trace’s data does not fall within the range of one of these benchmarks, it fails Video Optimizer’s test. The suggested best practices tests are categorized into five types: File Download, Connections, HTML, Video and Other.

• If all of the best practice tests in a category pass, the whole category passes.
• If one best practice test in a category fails, the whole category fails.

At the bottom of the Video Optimizer Best Practices / Results tab you’ll find a section called ‘Tests Conducted’. This is a summary of how your trace performed for each of Video Optimizer’s Best Practices tests. By scrolling further down the tab, you will see detailed information about each test result, including a Learn More link that will take you to a Best Practices document which examines the development practice that is being tested in detail. Each failed result contains specific information that includes a hyper linked word or phrase. By clicking on this link, you will be taken to a specific location in the Overview tab or Diagnostics tab that has more detailed results corresponding to the failure.

6. Testing

Video Optimizer User Guide

The Video Optimizer User Guide helps you develop a testing strategy, shows you how Video Optimizer fits into that strategy, explains the test cases in Video Optimizer, and describes the best approach for using them to test your application.

For analysis, the Video Optimizer User Guide describes methods for collecting an application trace using the Video Optimizer Data Collector, how to install, launch, and open a trace in the Video Optimizer Data Analyzer, and contains a full reference of the tabs, menus, options, charts, graphs, and statistics in Video Optimizer.

For best practices, the Video Optimizer User Guide describes each of the tests that are used to evaluate an application, and provides examples to help you interpret the detailed results generated by Video Optimizer.

AT&T Video Optimizer User Guide

This document provides guidance on how to use Video Optimizer to test an application.

7. Effective Testing

To get the most informative test results from Video Optimizer, it’s important to capture trace data that represents how your users really use your app.

To do this, you need a clear testing strategy that takes the following issues into account:

• Your app’s major user types and user behaviors.
• How quickly or slowly users execute functions in your app.
• The features of your app that generate the most network activity.
• Other applications and device peripherals your app uses.

When using Video Optimizer, it’s important to capture these different scenarios in separate traces. Organizing your testing strategy into distinct user scenarios and collecting traces for each of them will make it easier to narrow down areas that you’d like to improve.

In general, when testing any scenario with Video Optimizer, you should always collect one trace each of the following distinct states:

Active Scenario

Use your app for 20 minutes the same way your users would. Even better, enlist a friend to use your app on your test device, while you document the timing and execution of the functions they use.

Idle Scenario

Launch your app and leave it idle for 30 minutes.

The idle trace is a bit like the control of your testing experiment — it helps you gauge the amount of baseline network activity and battery use that your app generates independent of using the app itself.

For more information about planning and testing user scenarios, including scenarios for specific app types, see the following tutorials and guides.

• Video Optimizer User Guide
• Best Practices Guides from App Quality Alliance (AQUA)
• Five Strategies for Performance Testing Mobile Applications (from SOASTA)

9. Release Notes

Before you download Video Optimizer 5.3, make sure you meet the following system requirements for your operating system:

Video Optimizer 5.3 System Requirements & Software Prerequisites

• At least 4GB of RAM but suggested is 8GB
• Java 17 or above
• For Android developers, Android SDK Level 24 or above
• VLC media player 3.x.x or higher
• FFMpeg (including FFProbe)
• Windows requirements
  • Wireshark (Install Npcap addon with Winpcap API-compatible mode)
• Mac requirements
  • Brew (or any similar package manager)
  • Ifuse
  • MacFuse (formerly known as OSXFuse)
  • Libimobiledevice & ideviceinstaller
  • For iOS developers, use latest version of Xcode and OS X
  • Wireshark
• Linux requirements
  • For Ubuntu 18.04.x LTS (and newer) users, use VLC media player version 3.x.x
  • For Ubuntu 16.04.x LTS (and older) users, use VLC media player version 3.x.x up to 3.0.8
  • Wireshark

This release includes the following new features and enhancements:

• User can now export header-only PCAP files (with payloads removed) which are dramatically smaller than the original files, and in many instances just as useful for analysis in Wireshark. This feature is available both from the Video Optimizer Tools menu, and from the command line interface.
• New columns in the Flows summary table now display the type of Flow grouping (by SNI, domain name or IP address) and the value of the common SNI, domain name, or IP address.
• User is no longer limited to 26 Flow Groups. After groups A-Z are assigned, naming continues with AA through ZZ, followed by AAA though ZZZ.
• Video Optimizer now automatically restarts after an out-of-memory crash and notifies the user of the reason for the restart.

Known Issues in Release 5.3

• For attenuated trace collection, there can be performance and network issues when switching between videos or applications.
• PCAP header-only export currently does not support PCAPNG files.
• Activating a new flow group by clicking on an un-selected check box may result in an inaccurate SNI value being populated in the Flows Summary table below. Workaround is to activate a new Flow group by selecting the row and right click to "Assign selection to a group".
• Editing the color of a flow group will not get saved in the trace folder immediately. To ensure that it gets saved, an additional change must be made in the table, such as editing a label, adding a flow group, or changing another group's color.
• After Flow group Z is assigned, all subsequent Flow groups, starting with AA, are assigned the same color.
• After using Time Range Analysis, some SNIs, domain names and accurate protocols may disappear from the Flows table. These will be restored by reloading the trace.
• In the Flows tab: Flows table and Flows summary, the peak kbps value is displayed incorrectly when the scale is set to 5s in the Diagnostics tab graph.
• Secure collection is still done using the old VPN collector implementation. To differentiate the legacy application from the current version of the VPN collector, the legacy VPN collector has a lock symbol on the icon.

Past Release Notes