PPM vs TGA: technical differences
PPM and TGA are both uncompressed-pixel formats from the early days of computer graphics, and converting between them is close to a byte shuffle. Pixohub reads the PPM's RGB rows (top-down) and writes a 32-bit TGA in BGRA order, flagged as top-left origin, with an opaque alpha channel.
Because the output is 32-bit, the TGA is a third larger than the source P6: width × height × 4 bytes plus an 18-byte header. A 1024 × 1024 PPM of 3 MB becomes a 4 MB TGA. The alpha is 255 everywhere, since PPM has no transparency to carry over.
Inputs are limited to P6 at 8 bits and P3 at any maxval. The output is uncompressed TGA type 2, which almost every TGA loader supports, including the minimal ones found in OpenGL tutorials and small engines.
| PPM (Portable Pixmap (Netpbm)) | TGA (Truevision TGA (Targa)) | |
|---|---|---|
| Compression | None (raw binary P6 or ASCII P3) | None or lossless RLE |
| Colour depth | 8 or 16 bits per channel, RGB only | 8, 16, 24 or 32 bits per pixel |
| Transparency | None | 8-bit alpha in 32-bit files |
| Animation | None | None |
| Metadata | Comment lines in the header only | Optional image ID and extension area |
| Typical file size | Very large — exactly width × height × 3 bytes plus a header | Large — close to raw pixel size |
| Support | Image-processing libraries, Netpbm, GIMP; not browsers | Game engines, 3D and video tools; browsers cannot display it |
When to convert PPM to TGA
Textures for a hobby OpenGL or game-engine project
Many tutorials ship a tiny TGA loader. If your procedural texture generator writes PPM, converting gives you a texture those loaders can read without changing your generator.
Feeding legacy game or mod tools
Older engines and their tools often expect TGA. Procedurally generated skyboxes, noise maps or terrain textures from a PPM-writing script can be converted for them.
Testing your own TGA writer
Graphics students implementing a TGA encoder can compare their output against this one. Pixohub writes the top-left origin flag (descriptor byte 0x28) with uncompressed BGRA.
What converting PPM to TGA keeps and loses
What you keep
- Exact 8-bit RGB values.
- Resolution and orientation, recorded with the top-left origin flag.
What you lose
- PPM header comments.
- Precision above 8 bits per channel.
- A little size efficiency: the 32-bit TGA adds an opaque alpha byte per pixel.
Tips for better PPM to TGA results
- If a minimal TGA loader shows your texture upside down, it ignores the origin flag and assumes bottom-up. Flip the texture's V coordinate or the image itself.
- Need transparency? Generate it in your program and write PNG or TGA directly. PPM can't store alpha for the converter to pass on.
How this converter works
Pixohub decodes your PPM and encodes the TGA entirely inside your browser, using a bundled PPM decoder because browsers cannot open PPM natively. Nothing is uploaded, so the conversion is private by design and as fast as your device.
Need more? Shrink the result with the image compressor, change its dimensions with the image resizer, or convert a whole folder at once with bulk format convert.