Amazon Elastic Transcoder FAQs

General

Format Support

Pricing

Security

Service leval Agreement (SLA)

General

Q: What is Amazon Elastic Transcoder?

Amazon Elastic Transcoder is a highly scalable, easy to use and cost effective way for developers and businesses to convert (or “transcode”) video files from their source format into versions that will playback on devices like smartphones, tablets and PCs.

Q: What can I do with Amazon Elastic Transcoder?

You can use Amazon Elastic Transcoder to convert files from different media formats into H.264/AAC/MP4 files at different resolutions, bitrates, and frame rates; create thumbnails; and set up transcoding pipelines to transcode files in parallel.

Q: Who is Amazon Elastic Transcoder for?

Amazon Elastic Transcoder is for any customer with media assets stored in Amazon S3. Some examples are developers creating apps or websites that publish user-generated content, enterprises and educational establishments converting training and communication videos, and content owners and broadcasters needing to convert media assets into web-friendly formats.

Q: Why should I use Amazon Elastic Transcoder?

Amazon Elastic Transcoder manages all the complexity of running media transcoding in the AWS cloud. Amazon Elastic Transcoder enables you to focus on your content, such as the devices you want to support and the quality levels you want to provide, rather than managing the infrastructure and software needed for conversion. Amazon Elastic Transcoder scales to handle the largest encoding jobs. As with all Amazon Web Services, there are no up-front investments required, and you pay only for the resources that you use. We offer a free tier that enables you to explore the service and transcode up to up to 20 minutes of SD video or 10 minutes of HD video a month free of charge. To see terms and additional information on the free tier program, please visit the AWS Free Usage Tier page.

Q: How do I get started with Amazon Elastic Transcoder?

You can sign up for Amazon Elastic Transcoder through the AWS Management Console. You can then use the console to create a pipeline, set up an IAM role, and create your first transcoding job. To help you test Amazon Elastic Transcoder, the first 20 minutes of SD content (or 10 minutes of HD content) transcoded each month is provided free of charge. Once you exceed the number of minutes in this free usage tier, you will be charged at the prevailing rates. We do not watermark the output content or otherwise limit the functionality of the service, so you can use it and truly get a feel for its capabilities. To see terms and additional information on the free tier program, please visit the AWS Free Usage Tier page. If you do not have an AWS account, you can create one by clicking the Sign Up button at the top of this page.

Q: How do I use Amazon Elastic Transcoder?

To use Amazon Elastic Transcoder you need to have at least one media file in an Amazon S3 bucket. The easiest way to use Amazon Elastic Transcoder is to try it through the console. Create a transcoding pipeline that connects the input Amazon S3 bucket to the output Amazon S3 bucket. Create a transcoding job that will transcode your media file, choose a transcoding preset (a template), and submit the job. Your transcoded file will appear in your output bucket once it has been processed.

Q: What tools and libraries work with Amazon Elastic Transcoder?

Amazon Elastic Transcoder uses a JSON API, and we provide SDKs for Python, Node.js, Java, .NET, PHP, and Ruby. You can see a full list of our SDKs here.

Q: Can I use the AWS Management Console with Amazon Elastic Transcoder?

Yes. Amazon Elastic Transcoder has a console that is accessed through the AWS Management Console. You can use our console to create pipelines, jobs, and presets as well as manage and view existing pipelines and jobs.

Q: How do I get my media files into Amazon S3?

There are many ways to get content into Amazon S3, from the simple web-based uploader in the AWS Management Console to programmatic approaches through APIs. For very large files, you may wish to use AWS Import/Export, AWS Direct Connect, or file-acceleration solutions available in the AWS Marketplace. For more information please refer to the Amazon S3 documentation.

Q: How do I retrieve my media files from Amazon S3?

You can retrieve files from Amazon S3 programmatically, using the AWS Management Console or a third party tool. You can also mark Amazon S3 objects as public and download them directly from Amazon S3.

Q: Can I set S3 permissions and storage options?

Amazon Elastic Transcoder enables you to specify which users, groups, and canonical IDs you want to grant access to your transcoded files, thumbnails and playlists, as well as the type of access that you want them to have. You can also specify whether to store transcoded content using Standard or Reduced Redundancy Storage. Please refer to Amazon Elastic Transcoder documentation for further information.

Q: Can I use a Content Distribution Network (CDN) to distribute my media files?

Yes. You can easily use CDNs to distribute your content; for example, you can use Amazon CloudFront to distribute your content to end-users with low latency, high data transfer speeds, and no commitments. You can use an output bucket that contains your transcoded content in Amazon S3 as the origin server for Amazon CloudFront. For more information, please visit the detail page for Amazon CloudFront.

Q: How long does it take to transcode a job?

Jobs start processing in the order in which they are received in a pipeline. Once a job is ready to be transcoded, many variables affect the speed of transcoding, for example, the input file size, resolution, and bitrate. For example, if you were to submit a 10 minute video using the iPhone 4 preset, it would take approximately 5 minutes. If a large number of jobs are received they are backlogged (queued). Please note that the transcoding speed may be different between regions.

Q: When will my job be ready?

You can use Amazon SNS notifications to be informed of job status changes. For example, you can be notified when your job starts to transcode and when it has finished transcoding. For more information on Amazon SNS notifications, please see the detail page on Amazon SNS.

Q: How many jobs are processed at once?

Transcoding jobs are queued and are processed in parallel according to system capacity. You control the parallel processing of jobs through transcoding pipelines.

Q: How many jobs can I submit?

Currently, we allow 1,000 active jobs per pipeline. Once you exceed this limit, you will receive a 429 Rate Limit Exception. If you require this limit to be raised, please contact us here.

Q: Can I create multiple outputs per job?

Each transcoding job relates to a single input file and can create one or more output files. For example, you may wish to create a high- and low-resolution rendition of the same input file and could do so as part of a single transcoding job. You can have up to 30 outputs per transcoding job.

Q: What is a transcoding pipeline, what can I use it for, and how many can I have?

A transcoding pipeline is a queue that contains transcoding jobs. You can have up to four transcoding pipelines per AWS account, so you can transcode more than one job at a time. You can use pipelines in different ways. Some customers may choose to assign files of different durations to different pipelines, others may want to use a pipeline for a specific type of output. Another way to use pipelines is to keep one empty at all times for high-priority jobs. You can have up to four transcoding pipelines per account. If you require more pipelines, please contact us here.

Q: What are transcoding presets?

A preset is a template that contains the settings that you want Amazon Elastic Transcoder to apply during the transcoding process, for example, the codec and the resolution that you want in the transcoded file. When you create a job, you specify which preset you want to use. We provide presets that create media files that play on any device and presets that target specific devices. For maximum compatibility, choose a “breadth preset” that creates output that plays on a wide range of devices. For optimum quality and file size, choose an “optimized preset” that creates output for a specific device or class of devices.

Q: What do I do if none of your transcoding presets work for me?

You can create your own custom presets based on an existing preset. Once you create your own custom preset, it is available across your AWS account for the Amazon Elastic Transcoder service within a specific region. For more information on presets, please refer to the Amazon Elastic Transcoder Developer Guide.

Q: How many transcoding presets can I have?

In addition to the system presets, you can define up to 50 custom presets. If you require more custom presets, please contact us here.

Q: Why do I need to assign a role to a transcoding pipeline?

Amazon Elastic Transcoder uses AWS Identity and Access Management (IAM) roles to enable you to securely control access to your media assets. The IAM role sets a policy that defines what permissions you have for accessing Amazon S3 resources. You can assign different roles to different pipelines, and an IAM administrator can create specific roles for use with Amazon Elastic Transcoder. More information about IAM can be found here.

Q: How can I configure roles to be more restrictive?

You can use the AWS Management Console to edit and create new IAM roles. IAM roles that are created by Amazon Elastic Transcoder are visible in the AWS Management Console and can also be edited.

Q: How do I use notifications?

Amazon Elastic Transcoder uses Amazon SNS to notify you of specific events. You can choose to be notified about jobs that start to process, jobs that complete, warnings, and errors. Each event type is assigned to an SNS topic, and you can use the same topic or different topics for each event. The Amazon Elastic Transcoder console will create an SNS topic for you or you can specify an existing one.

Q: Why does my job keep failing?

The most common reason for jobs to fail is that the input file is corrupted in some way. If you receive an error about the format not being supported, we are unable to decode your source file and we’d love for you to tell us more about on our forum.

Q: Do you support encryption or DRM?

Amazon Elastic Transcoder focuses on transcoding operations only, so we do not support DRM or encryption. However, offerings from partners are available through the AWS Marketplace.

Q: How can I generate more than one thumbnail per job?

You can specify a thumbnail creation interval in seconds to create one thumbnail every n seconds. To create thumbnails in more than one size, you need to create different jobs.

Q: Can I reserve a transcoder for my exclusive use?

Amazon Elastic Transcoder provides a shared transcoding service and does not enable a transcoder to be reserved or allocated to an individual customer.

Q: Do I need to pay license fees?

We have licensed relevant intellectual property from the applicable patent pools for transcoding content. Like any other transcoder, customers are responsible for evaluating and, if necessary, securing licenses for distribution of content in various formats.

Q: Do you support live encoding?

Amazon Elastic Transcoder is a file-based transcoding service and does not support live transcoding.

Q: How do I deliver my transcoded content?

There are several ways to deliver content. The simplest is through progressive download, where an end-user downloads the file from a site. Another approach is to use a streaming server - see the AWS Marketplace for more information. In either case, you can provide end users with a better experience using a CDN like Amazon CloudFront. For more information on streaming, using Amazon CloudFront, please refer to this document.

Q: Are there limits to the service?

Customers are limited to four transcoding pipelines, 50 transcoding presets and 1,000 active transcoding jobs per AWS account.

Q: How do I increase service limits?

If you require an increase in the service limits, please contact us here.

Q: Where is Amazon Elastic Transcoder available?

Amazon Elastic Transcoder is available in the following AWS regions: US East (N Virginia), US West (Oregon), US West (N California), EU (Ireland), Asia Pacific (Tokyo), and Asia Pacific (Singapore).

The service operates standalone in each region, so jobs created in one region may not be transferred to another region.

You can create a transcoding pipeline in one region that would specify Amazon S3 buckets in another region. However, if you choose to do this, you should be aware that you will incur Amazon S3 transfer costs when content is read from or written out to an Amazon S3 bucket in a region other than the one where the transcoding work is taking place.

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Format Support

Q: What input formats do you support?

We support popular web, consumer and professional media formats. Examples include 3GP, AAC, AVI, FLV, MP4 and MPEG-2. If there is a format that you’ve found does not work, please let us know through our forum.

Q: Where can I find a comprehensive list of support formats?

We add new input formats on an ongoing basis, so such a list would age quickly. Please take advantage of our free tier and console to try a format not mentioned above and if you run into problems, please let us know!

Q: For MP4 files, do you support "fast start"?

We locate the MOOV atom for an MP4 at the start of the file so that your player can start playback immediately without waiting for the entire file to finish downloading.

Q: Do you support Apple ProRes?

We do not support reading Apple ProRes files at this time.

Q: Why do you only support H.264 and WebM output?

We asked customers which formats they are most interested in transcoding to and the majority wanted H.264 and WebM. We also support MPEG-2 TS as an output container for H.264 video and AAC audio.

Q: Do you support surround sound formats?

The audio portion of the transcoded output from Amazon Elastic Transcoder is two-channel AAC.

Q: Do you support audio channel remapping?

If the source file contains multi-channel audio, the output will contain the first two channels, which are frequently left and right audio tracks.

Q: Do you support closed captions?

Amazon Elastic Transcoder does not currently support closed captioning of content.

Q: Can I get segmented output for HTTP Live Streaming (HLS)?

Amazon Elastic Transcoder supports the creation of HLS v3 filesets and playlists. You can specify an input file and Amazon Elastic Transcoder can create a set of segmented output renditions at different resolutions and bit rates, and a corresponding M3U8 playlist file all stored in Amazon S3. You can then use Amazon CloudFront to deliver these to players that support HLS v3, like Apple iOS devices, Android devices and browser-based players like JW Player.

Q: How do I create content for HLS output?

There are two steps:

1. Create a transcoding job containing outputs for each HLS stream. You can use one of our supplied HLS system presets or create your own.
2. Create a playlist that references the outputs. You should make sure that you order your bit rates in ascending order per the HLS specification. Once your transcoding job has completed, the output bucket specified by the transcoding pipeline will contain your master playlist, stream fragments and playlist for each set of stream fragments. Pointing an iOS device to a URL specifying the location of this content will play back the content and dynamically select streams based on network conditions. For example, you could make the bucket publicly readable and open the corresponding URL to the M3U8 master playlist on your iOS device.

Q: Why is the H.264 or AAC parameter that I want to change not exposed by the API?

In designing Amazon Elastic Transcoder, we wanted to create a service that was simple to use. Therefore, we expose the most frequently used H.264 and AAC codec parameters. If there is a parameter that you require, please let us know by letting us know through our forum.

Q: What settings do I use to preserve the dimensions of my video?

Use the following settings in your custom preset:
MaxWidth: auto; MaxHeight: auto; SizingPolicy: ShrinkToFit; PaddingPolicy: NoPad; DisplayAspectRatio: auto

Q: How do I scale my output to a specified width and set the height to preserve the aspect ratio of the source content?

Use the following settings in your custom preset:
MaxWidth: [Desired Width]; MaxHeight: auto; SizingPolicy: Fit; PaddingPolicy: NoPad; DisplayAspectRatio: auto

Q: How do I limit the height or width of a video without stretching the output to fit my set limit while preserving the input aspect ratio?

Use the following settings in your custom preset:
MaxWidth: [Desired Width Limit]; MaxHeight: [Desired Height Limit]; SizingPolicy: ShrinkToFit; PaddingPolicy: NoPad; DisplayAspectRatio: auto

Q: What settings should I use to create a preset that causes the output video to fill the screen without distortion, if necessary cropping some of the edges ("center cut")?

Use the following settings in your custom preset:
MaxWidth: [Desired Width]; MaxHeight: [Desired Height]; SizingPolicy: Fill; PaddingPolicy: NoPad; DisplayAspectRatio: auto

Q: What settings should I use to create a preset that causes the output video to fill the screen without cropping any image area, if necessary distorting the image ("squeeze" or "stretch")?

Use the following settings in your custom preset:
MaxWidth: [Desired Width]; MaxHeight: [Desired Height]; SizingPolicy: Stretch; PaddingPolicy: NoPad; DisplayAspectRatio: auto

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Pricing

Q: How much does Amazon Elastic Transcoder cost to use?

Pricing for Amazon Elastic Transcoder is described here. Our pricing does not require any commitment or minimum volume of jobs. We also offer a free tier that enables you to explore the service and transcode up to up to 20 minutes of SD video or 10 minutes of HD video a month free of charge. To see terms and additional information on the free tier program, please visit the AWS Free Usage Tier page.

Q: How are jobs charged?

Transcoding jobs are charged according to the duration of the content. For example, media that lasts 60 minutes costs twice as much as media that lasts 30 minutes. High definition (HD) content costs twice as much as standard definition (SD). The minimum charge for a job is one minute. We do not charge for thumbnail generation, for API calls, or for Amazon S3 transfer within the same region.

Q: Why are HD jobs more expensive than SD jobs?

HD content is both larger and more computationally intensive to transcode. Consequently, our costs are higher when working with HD content. For Amazon Elastic Transcoder, SD content is anything up to 720 pixels high (720p). Anything greater than 720 pixels high is considered to be HD.

Q: Do you charge for failed jobs?

Our policy is to forgive customers for failed jobs unless the number of failed jobs becomes excessive.

Q: Is it cheaper to use multiple outputs per job than to use separate jobs?

When you use multiple outputs per job, transcoding costs remain the same as if you submitted multiple jobs for each output. However, the processing time will be quicker for larger jobs since the source file is only being transferred from your S3 bucket to Amazon Elastic Transcoder once.

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Security

Q: Are my media assets secure?

You are in complete control of your media assets because they are stored in your own Amazon S3 buckets. You use IAM roles to grant us access to your specific Amazon S3 bucket.

Q: Can I provide you with encrypted assets?

Currently, Amazon Elastic Transcoder requires you to provide unencrypted input files.

Q: What are the best practices for securing my media?

Please refer to our AWS Security Best Practices whitepaper.

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Service Level Agreement (SLA)

Q: Does Amazon Elastic Transcoder offer a Service Level Agreement (SLA)?

Amazon Elastic Transcoder does not offer an SLA at this time.