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Working with 16:9 stills saved from video in VS11.5+

Posted: Wed Apr 30, 2008 11:29 am
by Clevo
It was hard to work-out an effective title for this missive :oops: ...and I'm not sure I'm posting this in the correct forum...

Have recently started shooting video in SD 16:9 aspect ration in my Panasonic NV-GS180.

What I wanted to do was save some frames as stills which gave me BMP images with the frame size of 720x576 which is correct.

Importing this image so I can manipulate it with some effects in PhotoImpact X3 it opens as a BMP in 720x576...which is correct but as a 16:9 aspect ratio the image was of course squashed.

To correct this I converted the image to 720X348 which then corrected the squashed look.

I then imported this image into VS again to us in the video project. It matches perfectly and I was able to continue with exactly what I had in mind for this effect.

I haven't finished the project yet nor created a test video file but I have a sneaking suspision I have missed something or perhaps I could have done this better when I captured the still from the video.

The questions are:

Am I going to face issues with the video created later on?

Could I have done this better or a different way?

Advice appreciated.

Posted: Wed Apr 30, 2008 11:50 am
by jparnold
When you save a frame shot at 16:9 aspect ratio the output stills should be 1024 X 576 pixels NOT 720 X 576 that is why they appear squashed when imported into an image editor.

Have you set the project properties to (aspect ratio) 16:9? You can do this when VideoStudio opens (the first screen).

Posted: Wed Apr 30, 2008 12:14 pm
by Ron P.
Even with making sure the Project settings are for 16:9, you need to use the Command in the Tools menu, Save Current Frame. Using the Clips menu command of Save as Still image, will result in a 4:3 image, because the PC monitor is using 4:3 aspect ratio.

Posted: Wed Apr 30, 2008 12:28 pm
by jparnold
When I edit a video clip which was shot at aspect ratio 16:9 (PAL) and use the "save current frame" ALL resulting image files are 1024 X 576.
Also if I want to create say a MAP (of an area) to import into my video I have to create the image (with my image editor) with a size of 1024 X 576 pixels.

Clevo lives in Australia where the tv system is PAL and therefore the normal (4:3) image is 720 X 576 and wide screen (16:9) is 1024 X 576.

Posted: Wed Apr 30, 2008 12:37 pm
by Ron P.
Yes, I understand that, 4:3 aspect ratio is 1.33, whereas 16:9 is 1.77. I was pointing out, in VS if you use the command under the Clip menu, you get the image saved as a 4:3. When you use the command under the Tools menu (Save Current Frame), it will provide the image with the correct aspect ratio, in Clevo's case would be 1024 x 576, since 576 * 1.77 = 1024 (rounded off)..

Posted: Wed Apr 30, 2008 12:45 pm
by Clevo
jparnold wrote:When I edit a video clip which was shot at aspect ratio 16:9 (PAL) and use the "save current frame" ALL resulting image files are 1024 X 576.
Also if I want to create say a MAP (of an area) to import into my video I have to create the image (with my image editor) with a size of 1024 X 576 pixels.

Clevo lives in Australia where the tv system is PAL and therefore the normal (4:3) image is 720 X 576 and wide screen (16:9) is 1024 X 576.
It's why I mentioned the camera I am using thinking perhaps it may be a setting in the PC I am not using.

I have VS set to change Project properties when inserting the first clip to match.

My PC monitor is a 20" wide screen monitor with a native resolution of 1680X1050 which I believe is 16x9 (or 16.8x10.5)

So the recommendation is to use the grab from the tools menu...


Testing... Yes...that works much easier

Even though the Video attributes are:

Dv Video Encoder type 1
720x576 16:9

Thanks all

Posted: Wed Apr 30, 2008 1:21 pm
by Trevor Andrew
Hi

Its related to ¡¥Non square pixel rendering¡¦ applied to video.
Images use square pixels.

Pal 4 x 3 video relates to 720 x 576, sorry to say ¡§this size is not 4 x 3¡¨, the video is stretched to fit.

For images to fill the frame of a 4 x 3 you need 768 x 576 images.

You can identify the different image sizes if you change the preview screens background colour.

As mentioned widescreen 16:9 needs 1024 x 576 images to fill the frame even though a video using 16:9 is 720 x 576

Clear as mud

Posted: Thu May 01, 2008 11:56 am
by jparnold
Well (Vidoman) I have learned something. I didn't know that you could save a frame from a clip using the CLIP menu (and yes it does save as a 4:3 aspect ratio image). I have only ever used 'save frame as an image' from the TOOLS tab which always saves an image in the correct format (for me anyway).

To Clevo I suggest that you 'save frame as an image' from the TOOLS (drop down) menu.

Please try this and let us know if that fixes your problem.
The only other thing which could cause your problem is that the video camera does not record in TRUE 16:9 widescreen mode. I suggest that you try GSPOT (free download here) to determine what aspect ratio your video clip(s) is/are in.

Posted: Thu May 01, 2008 1:22 pm
by Clevo
jparnold wrote:Well (Vidoman) I have learned something. I didn't know that you could save a frame from a clip using the CLIP menu (and yes it does save as a 4:3 aspect ratio image). I have only ever used 'save frame as an image' from the TOOLS tab which always saves an image in the correct format (for me anyway).

To Clevo I suggest that you 'save frame as an image' from the TOOLS (drop down) menu.

Please try this and let us know if that fixes your problem.
The only other thing which could cause your problem is that the video camera does not record in TRUE 16:9 widescreen mode. I suggest that you try GSPOT (free download here) to determine what aspect ratio your video clip(s) is/are in.
Doing this from the tools menu works better for me.

I'm not convinced it's TRUE 16:9 considering the Video properties I post in my last response.

The funny thing is...even my thumbnails look squased in the Library but play properly in the preview window. This doesn't worry me

However I'll create a test video to see what happens with the way I did it before using the tools drop down menu

Posted: Fri Dec 05, 2008 7:46 am
by maxfrost01
Just reading through this thread which appears to address the problem I'm having - stills saved from a 16:9 movie appear to be distorted.
I'm going to try saving using the Tools option but meanwhile......

The Properties/Attributes reads "24 bits, 1440 x 1080, 16:9"

How can this be true? 1440 x 1080 is (according to my calculator) a ratio of 4:3! So which is right?

It looks like 16:9!! (except for when I save a still!)

Posted: Fri Dec 05, 2008 7:58 am
by maxfrost01
Just saved a clip using the Tools/Save Current Frame as Image command and I immedately get an image at 1920 x 1080 (which according to my calculator) IS 16:9! Using the "Save as Still Image" button I was getting stills of 1440 x 1080.
So once again the forum has solved my problem.

But my question posed in my previous post remains. How can the attributes be 1440 x 1080 AND 16:9?

Posted: Fri Dec 05, 2008 8:46 pm
by wiedmann
trevor andrew's post a few above yours answers this. Video pixels are not necessarily square. This means the aspect ratio can be different than the ratio of horizontal to vertical pixels. Think about anamorphic DVDs, for example. They have the same 4:3 pixel ratio as non-anamorphic DVDs, but present a 16:9 image.

Posted: Fri Dec 05, 2008 9:55 pm
by Trevor Andrew
Hi

If you wish to capture an image of your video as shown in the preview screen.

Select the frame
Switch to ¡¥project playback¡¦
Use ¡¥Tools¡X¡¥Save current frame as image¡¦

This will save the frame as seen in the preview screen.

Max

Video pixels are not square, they are stretched ---- rectangular.
For Pal---720 x 576 is the video frame size. This is not 16:9 1024 x 567 is.

Same goes for HD. 1440:1080 stretched to form 16:9, unless you use full quality HD 1920 x 1080, which is 16:9 (square pixels)

If you right click your video clip and select properties the frame size is the size you get when using ¡¥save as still image¡¦
If you use the top menu ¡¥clip¡Xsave as still image¡¦ will be the same size.

Only when switching to project playback will you get the correct still image aspect.