Replacement MTN (Thumbnailer) for H264 content (2 Viewers)

[azzuro]

For me,
a video file : 720x576 native
if set width 1920 for 2 rows =Movie is scaled to 1920x1536
for 2 rows = 1920x3072 resized to width set in config (width = 600 for quality) = 600x960 final output

 

[Jay_UK]

Hi there,

So assuminng 2 rows x 1 column.

Based upon the four scenarios:

Width is not specified (and video resolution known):
Video source is set to 720x576
Thumbnail is set to 720x576
Tile size will be (720/1)x(576/2) = 720x288
With this, the overall thumbnail aspect ratio and size is set to match the source
Once I produce the thumb, MePo does its magic and resizes it according to its own settings

Width is specified - lets assume 1920 (and video resolution known):
Video source is 720x576
Thumbnail is set to the specified width (height is calculated by using the specified width divided by the (video width/video height)
Tile size will be (1920/1)x((1920/(720/576))/2) = 1920x768
With this, the overall thumbnail aspect ratio and size is set to match the source
Once I produce the thumb, MePo does its magic and resizes it according to its own settings

Width is not specified (and video resoluton not known):
Thumbnail width is set to 1270 (height is calculated by using the specified width divided by 1.7777)
Tile size will be (1270/1)x((1270/1.7777)/2) = 1270x357
With this, the overall thumbnail aspect ratio and size is set to match the source
Once I produce the thumb, MePo does its magic and resizes it according to its own settings

Width is specified - lets assume 1920 (and video resolution not known):
Thumbnail width is set to the specified width - lets assume 1920 (height is calculated by using the specified width divided by 1.7777)
Tile size will be (1920/1)x((1920/1.7777)/2) = 1920x540
With this, the overall thumbnail aspect ratio and size is set to match the source
Once I produce the thumb, MePo does its magic and resizes it according to its own settings

Obviously if the source is smaller than the specified tile size, then FFmpeg will need to enlarge it.

I am more than happy to change the logic/mathematics if people feel the above is not correct. But like I said above, the height is halving to maintain the overal AR, therefore the individual tiles AR must change. If you want to keep the tiles AR, then the thumbs AR will change. Which is the best way ??

J.

 

[Jay_UK]

Hi guys,

A new release (V60) and source code are on the post first.

This release is still written in VB.Net - I had hoped to have it ported to C# tonight, but I'm a few hours behind schedule (C# is done, just need to test)

Please check the changlelog on post 1 for updates

J.

 

[azzuro]

Tested, thumbs are made, but same issue for me ..

 

[Jay_UK]

Hi there,

The issue will be the same... I haven't changed that part of it.

I am still struggling to understand how you think it should work??

Can you please explain (again) to me what/how you expect it to work??

I am not looking to do much more work on this program, instead I am looking to start work on the MePo code itself and see if I can further improve the great work Homey/Sebastiii have done.

Thanks,

J.

 

[azzuro]

Hi Jay, i think is better you test thumbnail me, is better of explain use MTN !

For me,
a video file : 720x576 native
if set width 1920 for 2 rows =Movie is scaled to 1920x1536
for 2 rows = 1920x3072 resized to width set in config (width = 600 for quality) = 600x960 final output

tM scale auto width of thumb
Formule : thumb width = (FinalWidth - Gap) / n° column

FFMPEG must extract format video
Width set : 600 / video format : 720x576 / GAP = 1

thumb view 1 column x 2 rows
thumb extract : 720x576
THUMB SET :
width for one thumb = 600 - 1x2x1(GAPx2xN°column) / 1 = 598
Height for one thumb = ((598x576)/720) - 1x2x1(GAPx2xN°column) = 476,4
output for one thumb 598x476 without GAP / 600x478 with GAP
COMPIL SET
Final for 2 column : 598x952 without GAP / 600x956 with GAP

MP make thumb from it, and leave file in storage ...

with this, aspect ratio is respected !

 

[Jay_UK]

Azzurro,

I have slightly enhanced my MTN to implement what I think you are after.

It now supports two modes:

Thumbnail Aspect Ratio (default option)
In this mode, the final thumbnail aspect ratio will match the source/video aspect ratio. This will mean the individual tile images may be distorted to ensure the overal AR is maintained for the thumbnail. The final thumbnail size should be quite consistant as it will be based on video aspect ratios (16:9, 4:3, etc)

Tile Aspect Ratio (custom option)
In this mode the final thumbnail aspect ratio will not match the source/video aspect ratio. Instead the individual tile image(s) aspect ratios are maintained. This may mean the overall thumbnail AR (dimensions) will be way off. I'm not sure how well MePo will handle it. In this mode having a large differential between rows and columns will make the overall thumbnail size "interesting".

To change from the default mode, to the TileAR mode, create a reg key call "keeptilear" and set it to "1" (or specify "-keeptilear") as a commandline option.

Let me know how you get on

Please see post one for the updated version (v61)

J.

 

[azzuro]

Hi Jay, Test V61
- For use MTN, MP must be have Admin Right, without this problem ! ( maybe my PC, tested on other)
- Format is OK, movie have "good size" but i don't understand, why you divided height by number or rows ? aspect ratio is not good !
- i think your output file have 100% quality of jpeg ! and 32bit color (24bit for TM)

i can't post MP thumb, problem with forum !?! i made ZIP

 

[Jay_UK]

Hi there,

I need to have the mtn_replacement.log file - this will give me the info to see what is happening.

I haven't even looked at JPG colour depth - Is this an issue??

J.

 

[azzuro]

it's only a problem for size ko! i don't know what is better !
i must remake test for file ...