HDR to TGA API
POST a .hdr to /v2/convert/hdr/to/tga and get a type 2 Targa: uncompressed, 8 bits per channel plus an alpha byte that is always 255 for a Radiance input. Rows are stored from the top.
- Endpoint
- POST /v2/
convert/ hdr/ to/ tga - Accepts
- hdr
- Sample timing
- 23 ms median of 5 runsHow we measure
- Request size
- Up to 10 MB on the Free plan or 100 MB on paid plans, all files together
Request and response
Every sample below ran against the API before this page was published. Set PDFCONVERSIONAPI_KEY to your key and run it as is.
curl -sS -X POST \
https://api.pdfconversionapi.com/v2/convert/hdr/to/tga \
-H "Authorization: Bearer $PDFCONVERSIONAPI_KEY" \
-F File=@lakeside-sunset-sky.hdr \
-o response.json
# FileData is base64. Save the first file in converted/,
# or print the JSON error.
if jq -e '.Files' response.json > /dev/null; then
mkdir -p converted
name=$(jq -r '.Files[0].FileName' response.json)
jq -r '.Files[0].FileData' response.json \
| base64 --decode > "converted/$name"
else
cat response.json
fiimport base64
import os
import requests
key = os.environ["PDFCONVERSIONAPI_KEY"]
response = requests.post(
"https://api.pdfconversionapi.com/v2/convert/hdr/to/tga",
headers={"Authorization": f"Bearer {key}"},
files=[("File", open("lakeside-sunset-sky.hdr", "rb"))],
timeout=180,
)
result = response.json()
if not response.ok:
raise SystemExit(f"{result['Code']}: {result['Message']}")
os.makedirs("converted", exist_ok=True)
for file in result["Files"]:
path = os.path.join("converted", file["FileName"])
with open(path, "wb") as out:
out.write(base64.b64decode(file["FileData"]))
print(path, file["FileSize"], "bytes")
import { mkdir, readFile, writeFile } from "node:fs/promises";
import { join } from "node:path";
const form = new FormData();
const file = "lakeside-sunset-sky.hdr";
form.append("File", new Blob([await readFile(file)]), file);
const url = "https://api.pdfconversionapi.com/v2/convert/hdr/to/tga";
const key = process.env.PDFCONVERSIONAPI_KEY;
const response = await fetch(url, {
method: "POST",
headers: { Authorization: `Bearer ${key}` },
body: form,
});
const result = await response.json();
if (!response.ok) {
throw new Error(`${result.Code}: ${result.Message}`);
}
await mkdir("converted", { recursive: true });
for (const file of result.Files) {
const path = join("converted", file.FileName);
await writeFile(path, Buffer.from(file.FileData, "base64"));
console.log(path, file.FileSize, "bytes");
}
{
"ConversionCost": 1,
"ConversionTime": 0.023,
"Files": [
{
"FileName": "lakeside-sunset-sky.tga",
"FileExt": "tga",
"FileSize": 320018,
"FileData": "AAACAAAAAAAAAAAAkAHIACAo…"
}
]
}Response from our test run on 2026-11-03. ConversionTime shows the median of 5 runs. FileData is shortened here; the real response carries the whole file as base64.
The sample, converted
The same file the code sends. Download the input and the output and compare them yourself.

- Input
- lakeside-sunset-sky.hdr (90 KB)
- Output
- lakeside-sunset-sky.tga (313 KB)
- Source
- A sunset sky panorama we drew in code and saved as a 400 × 200 Radiance RGBE file with run-length scanlines; the sun disc is 60.0. (CC0-1.0). How it was made
- Made by
- 2026-11-04, API build
9eeeb0640aba
Parameters
Send these as form fields next to the file. Names are case-insensitive. If you set one of the documented options below that we don't support yet, the request fails with a 400 that names it instead of returning a file made without it.
| Parameter | What it does |
|---|---|
ImageWidthinteger | Width after scaling; ImageWidth=120 gave a 120 × 60 Targa of 28,818 bytes.Values: 1–20000 |
ImageHeightinteger | Height after scaling; ImageHeight=100 came back 200 × 100, 80,018 bytes.Values: 1–20000 |
ScaleProportionsboolean, default true | false stretches into the exact box: 200 × 200 is 160,018 bytes. |
ScaleIfLargerboolean, default false | true blocks enlargement; ImageWidth=800 by itself produced 1,280,018 bytes. |
ScaleImageboolean, default true | false crops the upper-left 200 × 100 (80,018 bytes). |
ColorSpaceenum, default default | Gray or black-and-white values, still 32 bits per pixel and 320,018 bytes. rgb keeps the alpha byte too.Values: default, rgb, gray, monochrome; cmyk returns 400 |
TransparentColorstring | Sets alpha to 0 where a pixel matches exactly; #FFFFFF hits 333 clipped pixels, 101 at the sun and 232 along its streak on the lake.Values: #RRGGBB, R,G,B or a color name |
FileNamestring | Output name, lakeside-sunset-sky.tga by default. |
StoreFileboolean, default false | true gives a 3-hour URL. |
What carries over, and what doesn't
Kept
- The decoded pixels at 8 bits: the Targa matches the BMP route value for value
- Top-left row order, flagged in the image descriptor
- Raw pixels right after the 18-byte header, 4 bytes each, with no packets to decode
Lost or not yet supported
- Size: 320,018 bytes, 3.5 times the run-length coded 92,651-byte .hdr.
- Range above 1.0 and the 16-bit precision of the decode.
- One byte per pixel on an alpha channel that carries nothing for a sky.
- The file's
EXPOSUREand other header lines.
Limits
- One input file per request.
- 10 MB on the Free plan or 100 MB on paid plans including fields.
- 100,000,000 pixels or a 413.
- 1 to 20,000 px per side when resizing.
- A Targa side can't exceed 65,535 px: a 70,000 × 8 .hdr returned 413
TGA images can be at most 65,535 pixels on a side, and this one is 70,000×8. - 120 seconds.
Where teams use it
Skybox and background textures
Game mods and engines that import Targa backgrounds can take a converted sky panorama. Resize it with ImageWidth to a texture size in the same request.
Tools with simple loaders
A Targa reader is short to write, so small in-house tools can load a converted sky without also needing an RGBE decoder.
Questions
Why is there an alpha channel?
This route always writes 32-bit Targa, and ColorSpace=rgb does not remove the alpha byte. For a Radiance input every alpha value is 255, so the sky is fully opaque wherever the alpha is used.
Can I get a run-length compressed Targa?
No, the output is always type 2, uncompressed, with no option for type 10. That is 320,018 bytes for the 400 × 200 sky: 18 bytes of header and 4 bytes per pixel.
Is there a Targa 2.0 footer?
No. The file stops after the last pixel, with no TRUEVISION-XFILE footer, no ID field and no color map. Byte 17, the image descriptor, is 0x28: rows run from the top-left, with 8 alpha bits.
Convert your first HDR file in a minute.