HodrBoard 1.0.0 — illustrated guide

HodrBoard turns finished competition boards (PDF, PNG or JPEG) into new JPEG files at the exact pixel size of the brief, under the brief's byte limits, renamed from your registration code, and packed in a clean upload ZIP. A separate PRIVATE receipt records what it found and what it made. Everything runs in your browser from the extracted folder; nothing is uploaded.

What it does not do. HodrBoard cannot read words drawn as pixels (no OCR), so a name inside a drawing or logo is your responsibility. Its identity-term search is a review aid, not complete redaction. It does not check design rules and does not know whether a real competition will accept your files. It never uploads anything.

1. Prerequisites

Desktop Google Chrome. Tested: Chrome 152.0.7977.82 on Linux, in automated headless runs with a fresh temporary profile. Other browsers, operating systems and windowed use on other machines were not tested.
Extract the whole HodrBoard-1.0.0.zip to a folder. Keep HodrBoard.html next to its js, vendor and examples folders.
No installation, account or internet connection is needed.

2. First result in about a minute

Open HodrBoard.html in Chrome (double-click, or drag it into a Chrome window).
Press Load the Lantern Pier example. The fictional brief fills in: 3 boards, A2 landscape, 150 dpi, each board ≤ 4 MB, all boards ≤ 10 MB, code LP-0427, pattern {REG}-{N}.jpg, identity terms Morrow and jmorrow.
Read the findings on each board card, then press Fit and build.
Inspect each rebuilt board at 100 %, tick its confirmation and the acknowledgement, then download the upload ZIP and the private receipt.

HodrBoard start screen with the three steps Brief, Boards and Package — Start screen (1440 × 900). Brief on the left, boards in the middle, package on the right. Each step shows how many issues are open.

Three example boards with findings marked Not carried over — The example's three boards. The PNG's file name, the JPEG's EXIF Artist and XMP path, and the PDF's Author field contain “Morrow”. They are listed as *Not carried over*, because the new JPEGs are rebuilt from pixels and get none of that information.

Expected example result: LP-0427-1.jpg, LP-0427-2.jpg, LP-0427-3.jpg, each 3508 × 2480 px at 150 dpi. On the tested host, quality 95 put board 1 over 4,000,000 bytes, so all three boards were encoded at the common quality 90 (≈ 3.59 MB, 3.36 MB and 0.49 MB; 7.44 MB together). Byte counts can differ slightly with another Chrome version; the limits are always enforced on the exact files.

3. Enter your own brief

Boards required (1–8), sheet size (A0–A4, 24 × 36 in, 18 × 24 in or custom 50–1500 mm), orientation and resolution (72–300 dpi). The pixel size is shown below: pixels = round(mm ÷ 25.4 × dpi). A2 landscape at 150 dpi is 3508 × 2480.
Size limits: each board, all boards together (sum of the JPEG files) and, optionally, the final ZIP. Choose MB (1,000,000 bytes, the stricter reading) or MiB (1,048,576 bytes).
File names: registration code plus a pattern with {REG}, {N} or {NN}. Only letters, digits, hyphen and underscore are allowed, and the name must end in .jpg. Duplicate names, slashes, spaces and control characters are refused.
Identity terms: your name, studio, school, e-mail or user names, one per line (2–60 characters, up to 40). Matching ignores case and accents.
Save brief… writes a PRIVATE-brief.hodr.json file you can reopen with Open brief…. It contains your identity terms: keep it private.

Limits per board: at most 24,000,000 pixels and 8192 px per side; all boards together at most 96,000,000 pixels. So A1 at 150 dpi works, A2 at 300 dpi does not.

4. Add your own boards

Press Add finished boards (or drop files on it). Supported formats:

Format	Accepted	Refused with a reason
PDF	Ordinary unencrypted PDF; you choose the page. Crop box and page rotation are respected.	Layers (optional content), encryption, signatures, form fields/XFA, annotations or links on the chosen page, damaged files.
PNG	8-bit RGB or greyscale, opaque, upright; untagged, marked sRGB, or with a colour profile that behaves like sRGB.	16-bit, indexed colour, alpha/transparency, animation, an EXIF rotation or mirroring tag, HDR or wide-gamut encodings (cICP), colour profiles, primaries or gamma that do not behave like sRGB.
JPEG	8-bit baseline or progressive, RGB or greyscale, upright; untagged or with a colour profile that behaves like sRGB.	CMYK, 12-bit, lossless/arithmetic variants, colour profiles that do not behave like sRGB, “uncalibrated” EXIF colour without a profile, EXIF rotation other than “normal” (save it upright first).

How colour is checked. HodrBoard does not convert colour spaces, so it only accepts boards whose colours are already sRGB. An embedded colour profile is judged by what it does, never by its name: HodrBoard reads its tone curves and primaries and compares the colours it produces with standard sRGB for every level of each channel and a 17 × 17 × 17 colour grid. The profile is accepted only if no tested colour differs by more than ΔE 1.0 (CIELAB). Profiles built from lookup tables are refused even when they are meant as sRGB. If your board is refused, convert it to sRGB in your editor and export again.

Choosing a PDF page. For a PDF with several pages, choose the page on its card (the first 500 pages are listed). The preview, size and findings are read again for that page; until this is finished the card says “reading page …” and building is blocked. If the chosen page is not supported, for example because it has a link, HodrBoard keeps the previous page and says why.

Each file can be up to 32 MiB; all files together up to 128 MiB; at most 8 boards. Order boards with ↑ and ↓; the order sets {N}.

List of refused files with plain-language reasons — Unsupported files are refused before decoding, with the reason and what to export instead. Nothing is added for a refused file.

5. Review findings and decisions

✓ Not carried over — the term was found in the file name or hidden metadata (EXIF, XMP, IPTC, PNG text, PDF document information or XMP). The rebuilt JPEG contains none of it.
⚠ Needs your decision — the term appears in the PDF's page text. HodrBoard cannot tell reliably whether that text is visible, so you decide: fix your layout and export again, or tick Intended (for example a place name). The decision goes into the private receipt.
Different proportions — if a board's shape differs from the sheet by more than 0.5 %, building is blocked until you tick Fit with white margin or replace the file. HodrBoard never crops or stretches.

Board cards showing a PDF text match that needs a decision and a proportion warning — A PDF whose page shows “Studio Morrow” needs a decision; a PNG with different proportions needs the white-margin choice.

Raster text: the practice file board1-raster-name.png contains “drawn by J. Morrow” as pixels. HodrBoard reports nothing for it — by design it cannot. Your 100 % inspection is the safeguard.

6. Build and inspect at 100 %

Press Fit and build. Each board is rendered once at the exact pixel size on white, then encoded at qualities 95, 90 … 50. HodrBoard keeps the highest quality at which every board, the total and the ZIP (if set) meet the limits, and uses that same quality for all boards. It never lowers the pixel size to sneak under a limit.

Package step with measured quality table and 100 percent board viewers — Result with the measured byte table and a scrollable 100 % viewer per board. Downloads stay locked until every board is confirmed.

Upload ZIP and PRIVATE receipt buttons unlocked — After the confirmations and the acknowledgement, the upload ZIP and the PRIVATE receipt can be saved.

If even quality 50 is too big, HodrBoard says so and makes no package:

Not possible at the current settings message — Impossible limit (0.3 MB per board for a detailed A2): no package is offered.

Any change to the brief, the boards, their order, a page or a decision clears the result and cancels a running build, so you can never download a stale package.

7. Export, reopen and check

Upload ZIP (LP-0427-upload.zip in the example): only the renamed JPEGs, stored without compression, fixed 1980-01-01 dates, no comments. Each JPEG has only a JFIF header with the dpi, the image data and nothing else: no EXIF, XMP, IPTC, ICC profile or comments.
PRIVATE receipt (HTML + JSON): brief, original file names, findings and decisions, SHA-256 of inputs and outputs, measured quality table. Keep it for your records. Never upload it.
Reopen the ZIP in your system's archive tool and open the JPEGs in any image viewer to check them yourself before uploading on the competition's own site.
Your original files are only read, never changed.

8. Narrow screens and keyboard

The layout stacks into one column on narrow windows. Every control is a standard button, field or checkbox reachable with Tab; Enter or Space activates it.

HodrBoard at 390 pixels wide — 390 px wide.

9. Troubleshooting

Message	What to do
CMYK JPEG is not supported	Export as RGB/sRGB JPEG or PNG.
This PDF contains layers	Flatten or export without layers (or export a PNG/JPEG board). Hidden layers could carry content you cannot see.
Annotation(s) on the page	Export without links/comments, or export the board as PNG/JPEG.
Marked as rotated (EXIF orientation) or rotated or mirrored (PNG)	Open in your editor, save upright without the orientation tag, add again.
Embeds a colour profile … that is not standard sRGB	Convert the board to sRGB in your editor (not just assign a profile) and export again. The profile's name does not matter; its behaviour does.
HDR or wide-gamut colour encoding (cICP)	Turn off HDR/wide-gamut export and save an ordinary 8-bit sRGB PNG.
Primaries or gamma that do not match sRGB / uncalibrated colour	Export as sRGB; most editors call this “Convert to sRGB” or “Embed sRGB profile”.
Limit 24,000,000 pixels / 8192 px	Export at the brief's dpi, not higher.
Not possible at the current settings	Check the limits and unit; simplify very noisy textures; lower dpi only if the brief allows.
The example files are missing	Extract the whole ZIP; do not open HodrBoard.html from inside the archive.
Nothing happens on download	Check whether Chrome shows a download prompt or blocked-download notice, allow it, then press the button again.

10. Privacy

HodrBoard runs only in your browser tab. It makes no network requests (verified in testing: only file: and blob: addresses were used) and stores nothing after you close the tab. Brief files and receipts contain your identity terms and original names; keep them private.

11. Uninstall

Delete the extracted folder. HodrBoard installs nothing and leaves no settings behind; files you downloaded stay in your downloads folder until you delete them.

12. Limits, honestly

JPEG output only, in sRGB for screens — this is not a print colour proof. Inputs must already be sRGB (untagged or behaving like sRGB); other colour spaces are refused, not converted.
PDF pages are rendered by the bundled PDF.js 3.11.174; fonts that are not embedded are drawn with substitutes, so check text at 100 %.
No OCR, no logo detection, no design or rule checks, no portal upload, no guarantee of anonymity or acceptance.
Tested in Chrome 152 on Linux only.