batch to convert all image files into BMP format

[marcorocchini]

Hi, but sorry be patient because I'm a C*T

please I would like a batch that for all types of image sources (no video) try to convert it into .BMP 24 bit and TGA 32 bit in case of alpha channel is detected inside the source.

How can I do? thanks

[Bernix]

Hi,
1. Do you really need targa, or is tiff enough.
2. You can sort your images by bit depth in explorer.

Then use sorting by bit depth. And conversion to desired format for example in irfanview or in Faststone viewer (should be free for non commercial)
But I believe tiff is better. Or even PNG is good enough to keep alpha channel. BMP seems to me bit obsolete, but if is it your choice
PNG is also lossless format and with reasonable space saving. BMP is big file and simply obsolete. If there is software using bmp for input and not png it is not good. And for archiving is the choice obvious.

Edit: 24bit = 8bit and 32bit = 8bit + alpha channel. There can be image with 16bit per channel or even more, but it is not widely supported.

Bernix

[Bernix]

Just tested on png 8bpc + alpha. Size of png 180kB size of BMP over 60 000 kB. But of course both are 32 bit at the end.
But problem with bmp with alpha channel is not everything handle alpha channel correctly, just for clarification, I know, you don't want them keep alpha channel.

Edit: Just for my curiosity, how do you store 32bit picture now?
Edit2: And noticed tga doesn't show bit depth in explorer. Situation PNG 27kB, TGA 2552kB,Tif 84kB. And tif is able to hold 16 bits per channel.

Different software supports different lossless compression. Here is test. TGA is with RLE compression really small, but is limited in terms of bit depth.
Here is small picture just 8bit per channel + alpha channel PNG TGA and TIF

Bernix

[marcorocchini]

I need to convert in batch mode a lot of jpg pcx png tif and other image-formats into BMP. Not important TGA also because the alpha channel is not integrated in my sources.

I try to understand what is the way to automate this processing in a batch

[pandy]

oops - once again reading thread realized not video but image to image.

ffmpeg support some image formats so it can be used for image conversion, also specialized image processing software such as ImageMagick can be used for batch processing.

https://www.imagemagick.org/script/command-line-processing.php

@for %%a in (*.gif, *.png, *.jpg, *.tif) do (@magick "%%a" image.png "%%~na_.png")

btw - XNview or IrfanView offer simple GUI to perform mass conversion.

[Bernix]

Just for record.
There is one picture format using x265 or JCTVC encoder. It supports lossless, transparency, chroma subsampling from 4:2:0 to 4:4:4, bit depth 8-14, 5 types of color spaces. But it is not good for "printing" in fact it is not true in fact see printing size and ppi, just to save or for backup. So picture I posted is 333x458px 300x300 ppi with printing size 2,819x3,878 cm. But when you use this format of picture, you get picture 333x458px 72x72px ppi but printing size is 11,747x16,157 cm which is in ratio 300/72.
The example picture I posted is in lossless method chroma subsampling 4:4:4 with size 9,39 kB.
Any compression set to higher value reduce filesize significantly. In fact in most cases is it visually lossless at much higher value.
But there is problem with this format. More about it here
Xnview or Honeyview supports viewing and there is also possibility to view preview in explorer.
I mentioned it because it support batch and preserve metadata or transparency. I wrote this for no reason
Bernix

[Cornucopia]

BPG as a wrapper for hevc intra still encoding is probably never going to get far, now that Apple has thrown their weight behind the HEIF/HEIC format (hevc in mpeg iso base media wrapper). While still not universal, it is much more likely to be compatible with systems that already support hevc-encoded video. And Apple is now using it as their DEFAULT file format for photos! Both on macOs and iOs (newest version, higher-end hardware).

Scott

[Bernix]

Hi Scott,

BPG as a wrapper for hevc intra still encoding is probably never going to get far

I understand. But for me there is no problem if is it standard or not. I have backup several big files in bpg, because it is easy to convert them back to png without any quality loss. I am used to save them on the hdd (in bpg), when burned my images (in png and ai), that I make in adobe illustrator. Of course there is situation when lossless is much bigger than original file, when the file is with too much artifact because of compression. And of course nobody will print it to me bpg file. But when I really need to print it (when I lost original file that I have on dvd or blu-ray), so I simply encode the picture to desired format (PNG or PDF(i don't like PDF format for printing))
I understand the strategy to store photos in this or similar format. No quality loss and lots of space and bandwidth saved

Bernix

[jan5678]

xnconvert (from the same maker of xnview) might what you want, if it is for Windows though

Or NConvert (commandline) https://www.xnview.com/en/nconvert/

But i don't understand why you can't find this info yourself?
It ain't rocket science..

[pandy]

HEIC will play an important role in our future technology considering its ideal compression codec.

[FLAME]
Doubtful claim, please elaborate on this.
[/FLAME]

[Bernix]

I will stick with old good TIF, PNG for work and (just for storing of not so important images) -> BPG

Bernix

[pandy]

I will stick with old good TIF, PNG for work and (just for storing of not so important images) -> BPG

Ok, then next problem why BPG not HEIF (HEIC)? Seem BPG is even more sparse than HEIF.

[Bernix]

Hi Pandy,
that is because I already have plenty of images in this format and honey view and other programs can read it without problem. And I like BPGconv for plenty of option. Chroma, color space, Bit depth, encoder which I want to use x265 or JCTVC (is more effective surprisingly) etc. So why to convert these BPG images to HEIC when it supports alpha channel too, 8 and 16 bit depth, chroma subsampling 4:2:0, 4:2:2 and 4:4:4, color spaces YCbCr, RGB, YCgCo, YCbCr BT 709, YCbCr BT 2020, and if i want to send it to somebody, just convert them back to jpeg or png or let it be on reciever. I don't need lossless cropping and rotating by 90 degrees.
And I forgot it supports metadata also
For animation of course Tif or somebody prefer Tiff, and png which is enough for me.
I understand HEIC or HEIF as replacement for jpeg in mobile devices (in front line), but doubt it soon replace PSD, KRA and similar file formats for real work. And as intermediate work. 100 x (Open modify save). Of course it can work with lossless version, but what nowadays software supports it. And keep "archive of less or more useful images" in several format seems to me be uselessly.

Bernix

[cornemuse]

I have older version of this:

http://www.mindworkshop.com/gwspro.html

I use it mainly for batch conversions anymore.

-c-

[hello_hello]

I'm a bit late to the thread, but Irfanview has a batch conversion mode and it'll open just about any image format. It can also batch crop/resize and apply effects to images if that's what takes your fancy.

[Bernix]

Hi Hello_hello

I'm a bit late to the thread, but Irfanview has a batch conversion mode

The problem is OP demands also TGA conversion. And this is bit problem from my POV. Because there isn't any option parameters (but i can be wrong). So 8k picture saved as TGA is about 50MB. When same image saved in Xnview with RLE compression in TGA is just bit over 2MB.
But as I said, I can be wrong and just missed option for TGA in irfanview.

Bernix