Tutorial: Subtitling Basics
Subtitle Types:
Text based – means the rendering of subtitles is executed by the device (e.g. TV).
It is up to the device to draw the given text in the selected size, colors and font.
Subtitle text can be also encoded to allow characters for languages (e.g. Polish, Arabic) to be displayed correctly.
Image based – where subtitles are specified as an image and the device displays them it as is.
Advantage of this system is that devices do not need to process the text with fonts, encoding or formatting.
Presentation Types:
Time based – each subtitle text item is displayed based on the video’s timeline.
Example: 1 minute 43 seconds 12 milliseconds
Frame based – each subtitle text item is displayed based on the number of the video frame.
Example: frame=123
Note: The video rate or frames per second (FPS) of a video may change if the original video is transcoded to another format. This can often occur when converting a video from PAL (25.0 fps) to NTSC (23.97 fps). In this case, frame based subtitles prepared for PAL will not match the new NTSC video and subtitles will no longer be synchronized with the video.
Tip: Mezzmo will automatically convert subtitles to match the video’s original FPS frame rate.
How Mezzmo streams subtitles
External – subtitles are stored in separate files and streamed directly to your device. Popular formats are .SRT, .SMI and .SUB.
External subtitles may be text based such as the SubRip (.SRT) format, or image based such as the VobSub (.SUB) ripped from a DVD.
This is the most effective way for streaming subtitles for a video, since it does not require any processing by Mezzmo. Unfortunately, some devices are not capable of displaying external subtitles - for example, Sony Playstation PS3, Microsoft Xbox 360 and Sony Bravia TVs.
Embedded – subtitles are stored inside the video file (or video container) as a stream - in the same way that video and audio streams are stored inside the video file. Not all video container formats can have embedded subtitles and there are limitations what subtitle formats are supported for each video container format.
Some popular video containers that allow embedded subtitles are:
• Matroska (MKV) – has excellent embedded subtitle support. For example, text based subtitles such as SubRip (SRT), Advanced Substation Alpha (ASS) and SubViewer (SUB), or image based subtitles such as DVD/Bluray subtitles (VobSub).
• MPEG-4/3GP/MOV/M4V – allows Mpg4 text based XML subtitle format
• MPEG-2, MPEG-TS – allows DVD (VobSub) subtitles
• OGG – allowing SubRip (SRT) and others.
• AVI – allows image based XSub subtitles withing the DivX specification
Note: Support for displaying embedded subtitles varies between each device model from manufacturers. The the most popular video container with embedded subtitle support is Matroska (MKV). For example, devices from WD, Samsung and Panasonic will display embedded subtitles in MKV video files.
Tip: Mezzmo can automatically embed external subtitles files into a video container before streaming by “remuxing” (or inserting) the external subtitle into the transcoded video.
Tip: Devices typically can list list all the embedded subtitles onscreen for you to choose using the device’s remote control. This allows you to choose your preferred subtitle language.
Burning – subtitles are drawn (or superimposed) over the video frames in the video by Mezzmo before streaming.
Some devices (e.g. Sony Bravia TVs) cannot display external subtitles or embedded subtitles, so burning the subtitles into the video is the only way to display subtitles. Burning subtitles requires Mezzmo to fully transcode the video and this can require significant CPU and memory usage. Also, choosing another subtitle will require re-transcoding the video again. Note that the original video file is preserved so burning subtitles can be repeated as many times as required.
Tip: Mezzmo v3.1+ also burns subtitles into 3D movies.
3D-Subtitles - Side by Side, 3D-Subtitles - Top and Bottom:
http://www.conceiva.com/forum_faq/me...ubs-3D-SbS.png . http://www.conceiva.com/forum_faq/me...ubs-3D-TaB.png
Tip: Procedure of embedding or burning subtitles will create a temporary file, that will be used for streaming. Make sure the transcoded video file is deleted after changing subtitles settings or adding new external subtitle tracks
Detecting External Subtitles
External subtitles are automatically detected by Mezzmo when you add your video files into your Mezzmo library or when you maintain your Mezzmo library.
The external subtitle file must exist in the same folder as the video file and should have the first part of the file name as video file name (i.e. “paired”). For example:
- myvideo.avi - Video file
- myvideo.srt - SubRip subtitle file
- myvideo.txt - Subtitle file; format will be auto-detected by Mezzmo when reading the content
- myvideo.fr.sub - Subtitle file in French language
DVD or Bluray rip by ISO archive file, requires external subtitle file placed in the same folder and renamed to match the ISO archive file name (i.e. “paired”) and movie title index as detected Mezzmo library, for example:
- \video\myDVD.iso - DVD rip ISO archive file
- \video\myDVD_title1.fr.srt - SubRip subtitle file in French language for "My movie (1/2)"
- \video\myBluray.iso - Bluray rip ISO archive file
- \video\myBluray_title2.srt - SubRip subtitle file for "My movie (2/2)"
DVD or Bluray rip by file structure, requires external subtitle file placed in disk root folder, and renamed to match disk root folder name and the movie title index as detected Mezzmo library, for example:
- \video\myDVD\VIDEO_TS - DVD rip file structure
- \video\myDVD\myDVD_title1.srt - SubRip subtitle file for movie "My movie (1/2)"
- \video\myBluray\BDMV - Bluray rip file structure
- \video\myBluray\myBluray_title2.fr.srt - SubRip subtitle file in French language for movie "My movie (2/2)"
Tip: Where Mezzmo is looking for external subtitles:
- Select movie in Mezzmo library.
- Choose Menu / Edit / Properties -> Subtitles tab.
- Move mouse over Update Subtitles button. For a brief moment, dialog view will show the location for the external subtitles, for example:
"Search for: H:\Multimedia\The Fifth Element\The Fifth Element_title1*.*" will match two external subtitle files like:
"H:\Multimedia\The Fifth Element\The Fifth Element_title1.srt"
"H:\Multimedia\The Fifth Element\The Fifth Element_title1.fr.srt"
Mezzmo can detect over 30 text based formats. See the detailed list at:
http://www.conceiva.com/products/mez...matsupport.asp
Detected subtitles are listed by Properties dialog (Subtitles tab) for a video:
- In Mezzmo, select a video file.
- Click Edit / Properties to display the Properties dialog and click the Subtitles tab.
http://www.conceiva.com/forum_faq/me...p-External.png
Subtitles listed may have various formats, and it is recommended to verify your subtitles by previewing them:
- Select a subtitle track from the subtitle list.
- Click the Subtitle Setting button to preview the subtitle content.
External subtitle tracks may be disabled using the checkbox in the first column in the subtitle list. Unchecked subtitle tracks will not be used by Mezzmo for any subtitle processing or streaming.
Tip: How to add a subtitle manually:
- Click the Add Subtitle button.
- Select the subtitle file from your computer’s hard disk or NAS.
- Verify the subtitle content and click OK to accept the settings.
Note: If subtitles are not displayed properly on your devices, then it may be required to adjust the subtitle settings. Typically this means changing the language, font and code page. If Mezzmo reports reading errors, then the reason may be that the subtitle format may be unknown to Mezzmo or the subtitles may be corrupted. In this case, try to force the format using the Input format field.
Tip: Global settings allows to specify the way Mezzmo handles all subtitles, including your preferred subtitle language, fonts and code page.
- Click Tools / Options to display the Options dialog and go to the Subtitle page.
- Click the Global Settings button to specify the rules for processing all subtitles.
- Click the Settings button next to Preferred Languages to specify the rules for processing subtitles prepared in selected languages.
Detecting Embedded Subtitles
Embedded subtitles inside video files are automatically detected by Mezzmo when you add your video files into your Mezzmo library or when you maintain your Mezzmo library.
Mezzmo will also automatically embed external subtitle tracks into a transcoded video before streaming when “Stream embedded subtitles” checkbox is selected.
Subtitle tracks may be disabled using the checkbox in the first column of the subtitle list. Unchecked subtitle tracks will not be used by Mezzmo when a video is transcoded and subtitles may not be embedded into that movie. When all subtitle tracks are disabled, the transcoded video will not contain any embedded subtitles.
http://www.conceiva.com/forum_faq/me...p-Embedded.png
Note: Mezzmo lists all detected subtitle tracks - even if some of the subtitle formats are not supported by your devices.
Click the Subtitle Settings button to change the language and the title of the embedded subtitle.
Tip: Mezzmo will arrange the order of the embedded subtitle tracks to match your preferred language.
Tip: Click the Extract Subtitles button to extract the selected embedded subtitle track from the video file and save it as an external subtitle file on your computer. Mezzmo can extract popular formats such as SubRip, ASS and VobSub. Extracted subtitles will be used by Mezzmo for streaming as external files or burning into the video.
Per-Language Subtitle Settings
You can specify the subtitle settings for each of your preferred languages that you have specified in the Options dialog (Subtitles page).
- Click Tools / Options to display the Options dialog and go to the Subtitles page.
- Click the Add button, and add a new language to the “Preferred subtitle language” list.
- Order the list of languages using Up and Down buttons.
- Click the Settings button and specify subtitle settings for the selected language.
- Repeat the settings for each of the preferred languages.
Mezzmo automatically recognizes the language of external subtitles when the external subtitle file contains a special suffix language code. For example:
- myvideo.avi - Video file
- myvideo.fr.srt - Subtitle file in French language
- myvideo.ger.srt - Subtitle file in German language
- myvideo.Spanish.srt - Subtitle file in Spanish language
- myvideo-fr-cd1.srt - Subtitle file in French language
Language identifiers that Mezzmo detects:
- two letters code, as ISO-639-1 standard, commonly used by HTML pages on Internet, examples: pl, fr, en,
- three letter code, as ISO-639-2 standard, examples: pol, fra, eng
- name of the language, examples: Polish, French, English
- two letter country code, as ISO-3166 standard, examples: pl, fr, uk, us
Some subtitle formats like Sami or VobSub may have special tags with language specifications. For all these files, Mezzmo will read these special tags and detect the language automatically. These formats may also have many subtitle tracks inside the one external subtitle file. Deleting the external subtitle file may actually remove many subtitle languages from the subtitle list of the video.
Tip: Use Properties dialog (Subtitles tab) for a video to manually specify the language for each subtitle track if the language has not been detected automatically by Mezzmo.