Encoding vs Transcoding

[Mat1926]

Quote

Encoding, by definition, takes analog source content and converts it to a digital format, such as converting your old family Super8 films to DVD. In contrast, transcoding takes an existing digital format and converts it to a different digital format, as is the case when you take a Flash video and convert it to an adaptive bitrate format such as.... 

Source Click M3

 

My primary language is not English, so is this true? I am asking because I do convert videos/audios on my PC all the time, so I want to use the proper terms...

[AshleyAshes]

40 minutes ago, Mat1926 said:

Source Click M3

 

My primary language is not English, so is this true? I am asking because I do convert videos/audios on my PC all the time, so I want to use the proper terms...

Not really though the terms are used very sloppily.

 

But if one wants to be needlessly precise, 'Encoding' is the act of encoding something regardless of source.  Transcoding is to convert from one encoded format to another, where first the data is decoded from one datatype and then encoded into another datatype.

 

Though I imagine would would have to be in one sad, stupid, uber nerd 'Well, Technically!' fight to really debate the semantics of transcoding vs encoding.

[LAwLz]

Come to think of it, it's very hard to define them. I am not sure how I would define them (not sure if I am using them 100% correctly either), but I'll give it a try:

 

Encoder - A program that creates a file which adheres to a predefined format.

Decoder - A program that reads data and presents it to the user or a different program.

Transcoding - The use of a decoder and encoder together in order to convert data from one format to another.

 

Encoding:

• Talking into an analog microphone and the sound gets converted to something your computer understands. An encoder converted that analog signal to a digital one.
• Live streaming a video. Your computer generates an image, which then gets encoded into a format such as H.264 so that others can view it.

Decoding:

• Playing an MP3 file on your computer. A decoder takes the file saved and decodes it, and then that signal gets sent to your speakers.
• Playing a video. Your computer has a video file such as H.264, and then it has a set of instructions which converts the H.264 file into something that can be displayed on your monitor.

Transcoding:

• Taking your H.264 file, running it through a decoder, which passes the output to an encoder which generates a new file such as HEVC, or maybe even another H.264 file.

 

[kasugatei]

9 hours ago, LAwLz said:

Come to think of it, it's very hard to define them. I am not sure how I would define them (not sure if I am using them 100% correctly either), but I'll give it a try:

 

Encoder - A program that creates a file which adheres to a predefined format.

Decoder - A program that reads data and presents it to the user or a different program.

Transcoding - The use of a decoder and encoder together in order to convert data from one format to another.

 

Encoding:

• Talking into an analog microphone and the sound gets converted to something your computer understands. An encoder converted that analog signal to a digital one.
• Live streaming a video. Your computer generates an image, which then gets encoded into a format such as H.264 so that others can view it.

Decoding:

• Playing an MP3 file on your computer. A decoder takes the file saved and decodes it, and then that signal gets sent to your speakers.
• Playing a video. Your computer has a video file such as H.264, and then it has a set of instructions which converts the H.264 file into something that can be displayed on your monitor.

Transcoding:

• Taking your H.264 file, running it through a decoder, which passes the output to an encoder which generates a new file such as HEVC, or maybe even another H.264 file.

 

 

I am working for broadcasting devices and solutions development company and I would say that this is 99% correct but there is one small thing which bothers me. Encoders and decoders are not necessarily programs, they can be hardware devices as well. 

In the broadcasting industry you usually use encoder device when you have raw signal (eg. SDI) as an input and at the output you have eg. IP encapsulated TS (container used when broadcasting for TV, satellite etc.) with MPEG2/H264/HEVC video and eg. AAC audio. In that case companies usually use hardware based products because of the low encoding latency.