Commons talk:File types

BMP files

I am not asking for BMP support to be added, I am just curious whether there a specific reason WAV (uncompressed audio) files are supported while BMP (uncompressed pictures) aren't.

My closest guess would be that a tool to convert BMP to PNG was pre-installed on Windows since its early days. Given that the majority of computer users run Windows, they can convert BMP into PNG using the pre-installed Microsoft Paint. But Windows has no out-of-the-box tool to convert WAV to any other lossless format. Also, Windows Media Player didn't have out-of-the-box FLAC support until at least Windows 8 or 10, so WAV was the only lossless audio format natively supported by Windows for a long time.

Also, audio like WAV is streamed, not loaded in one piece, so slower loading might not be noticeable to a user with weak connectivity. Elominius (talk) 08:27, 14 February 2025 (UTC) (edited 09:37, 14 February 2025 (UTC))

I assume that is because BMP and PNG are both lossless so just formally PNG is much better than BMP. But if we talk about WAV it is usually a raw audio format provided "directly" by hardware so it is as close to original as possible while other audio formats are very lossy (often exploiting how people hear and cut a lot of original info). So to summarize, I think that adding bmp is useless because it will contain the same data, while wav contains much more info than compressed counterparts DustDFG (talk) 09:24, 21 November 2025 (UTC)

WAV supports encoding in more audio coding schemes than FLAC (which only does PCM), see en:WAV#Comparison of coding schemes. Trying to transcode non-PCM WAV into FLAC would lead to quality loss. pandakekok9 12:01, 27 November 2025 (UTC)

So what is more preferred lossless webp or png?

What to choose? DustDFG (talk) 10:11, 21 November 2025 (UTC)

WebP regardless of whether it's a lossless or lossy upload seems to always use JPEG for thumbnails in MediaWiki. If it's intended to be used in a wiki page you might be better off uploading it as a PNG to avoid the JPEG artifacts, especially if the image is something like a screenshot. pandakekok9 11:52, 27 November 2025 (UTC)

. . . except digital camera photographs

"PNG is good for practically anything except digital camera photographs." That's what most of our millions of pictures are, right? So, what is good for uploading digital camera photographs? Jim.henderson (talk) 06:40, 23 January 2026 (UTC)

@Jim.henderson: JPEG. If that is not clear from the text, please propose text changes that would make it more clear.   — 🇺🇦Jeff G. ツ please ping or talk to me🇺🇦 17:58, 23 January 2026 (UTC)