Picture Batch CR2 to PNG
CR2 to PNG
A CR2 is the raw file every Canon EOS body wrote between roughly 2004 and 2018, and the camera usually also saved a ready-made JPEG preview inside it. This page ignores that preview and decodes the sensor data itself, then writes a PNG that stores the result without any further loss — the format to use when the picture is going into an editor, a layout or an archive rather than straight to a screen.
Drop CR2 images here
CR2 files — or any of PNG, JPEG, WebP, AVIF, BMP, ICO, TIFF, GIF or camera raw (CR3, NEF, ARW, DNG, RAF, ORF, RW2). Everything runs on this device.
Or paste an image from the clipboard.
Your images never leave this device. They are decoded and re-encoded by your own browser, and the security policy on every page blocks this site from sending them anywhere.
Lossless, keeps transparency, universally supported, larger than modern formats.
PNG is lossless — it stores every pixel exactly, so there is nothing to trade away.
Images keep their original dimensions.
Images are turned upright from their own orientation data, and left that way.
Kept. PNG stores a full alpha channel, so cut-outs and soft edges come through exactly.
Exif is carried across where both formats can hold it. Nothing currently in the queue has any.
Decodes at the file's full resolution, interpolating missing colours when it has a colour filter array. Files already holding colour pixels need no demosaicing.
The value your camera recorded when the shutter fired — what you saw on the back of the camera.
Camera, lens, exposure and capture time are written into the PNG when those fields are present. The file details show whether GPS data exists, but coordinates are deliberately not written, and colour comes out as sRGB.
What happens to your image
File size depends mostly on the image itself.
| Property | Outcome |
|---|---|
| Transparency | Preserved: CR2 images have no transparency to lose. |
| Image quality | Preserved: Unchanged. Both formats are lossless, so every pixel comes through exactly. |
| Colour | Partly preserved: LibRaw develops the sensor data into eight-bit sRGB. The output uses that colour space; a source colour profile is not copied into the output. |
| Exif metadata | Partly preserved: When metadata is switched on, the camera, lens, exposure and capture time recorded in the raw file are assembled into a standard block and written into the PNG. Switch it off to remove them. The GPS position is shown to you in the file details and deliberately never written. |
| Orientation | Preserved: Applied to the pixels, and the tag is reset to upright afterwards so nothing rotates the image a second time. |
From lossless JPEG to lossless PNG
Inside the TIFF container of a CR2, Canon compressed the sensor readings with lossless JPEG — an obscure, genuinely lossless part of the JPEG standard that has nothing in common with the lossy JPEG used for photographs. Decoding it gives back the exact twelve- or fourteen-bit value each photosite recorded.
From there the picture has to be made: black level subtracted, white balance applied, the red, green and blue filter mosaic interpolated into full colour, the camera's colour matrix applied to reach sRGB, and a tone curve mapped. The PNG then stores that picture exactly, at eight bits per channel. Nothing after the decoder discards detail, which is the difference from converting to JPG.
The sRAW and mRAW variants some Canon bodies wrote with the same extension are already full-colour at reduced resolution, so they skip the interpolation step. They convert too, at the size they were recorded.
Choices the converter makes for you
Demosaicing uses adaptive homogeneity-directed interpolation, a well-established method that avoids most of the zipper and colour-fringe artefacts simpler methods leave on fine detail. It is not adjustable; the faster methods are visibly worse, and half resolution is the better way to trade quality for speed.
White balance defaults to what the camera recorded when you took the picture. Automatic white balance, computed from the image, is one click away and is often better on old files shot under tungsten or fluorescent light.
Automatic brightening is on, as it is in essentially every raw converter, because sensor data is recorded with headroom for highlights and renders about a stop dark without it. What is not applied: Canon Picture Styles, lens corrections, sharpening, or noise reduction beyond the decoder's defaults.
When PNG is the wrong choice
A PNG of a photograph is large. The eight-megapixel EOS 20D file this page is tested with is a 7 MB CR2 and becomes a 19 MB PNG at full resolution — nearly three times the size — and a detailed frame from a higher-resolution body is larger again. For sharing, uploading or viewing, the CR2 to JPG page gives a result a fraction of the size that looks the same.
PNG is also not a way to keep raw latitude. It is eight bits per channel, and highlights the tone curve has clipped stay clipped. Keep the CR2 files themselves as the archive, and treat the PNG as a high-quality working copy.
If something goes wrong
The file is refused as not being a CR2.
Identification is from the file's contents, and the contents say otherwise — usually a CR3 that was renamed, or a file that did not copy off the card completely.
What to do: The message says what the file really is. A CR3 converts on its own page; an incomplete copy needs copying again from the card.
The PNG is slightly darker or lighter than the camera's own JPEG.
The camera applied its Picture Style and its own brightness curve. This converter applies a standard curve with automatic brightening.
What to do: Expected. Adjust exposure in the editor you are handing the PNG to — it holds every decoded pixel exactly, so there is no compression to fight.
The row says the camera's embedded preview was used.
The sensor data could not be decoded, typically because the file is damaged or truncated, so the preview stood in.
What to do: Treat that PNG as a rescue, not a conversion. It is the camera's JPEG preview saved as PNG, with the camera's processing and compression already in it.
Questions
Why convert CR2 to PNG rather than to TIFF?
PNG opens in practically everything, including every browser, and is losslessly compressed by default. This tool does not write TIFF. If you specifically need sixteen-bit TIFF for editing, use a raw editor for that step.
Can I convert a folder of CR2 files to PNG at once?
Yes. Add them all, and the queue decodes them in parallel as far as the device's memory allows, with real progress per file. Download them one by one or as a ZIP with a manifest that records which camera each came from and how the sensor was read.
Are the camera and lens details kept?
With metadata on, the camera, lens, exposure and capture time are read from Canon's maker notes and written into the PNG's Exif chunk. Location data, if any, is shown but never written. Some older programs do not read Exif from PNG at all.