CHI Supplementary Materials

CHI collects the paper, the video figure, and every supplementary file together on the one submission deadline (September 10, 2026 for CHI 2027, per chi2027.acm.org, read 2026-07-08). There is no later supplement slot, so supplement production is deadline-week work that must be scheduled like writing. Everything uploaded is part of the anonymous review record; everything accepted ships to the ACM Digital Library beside the paper, permanently.

What goes where

The self-containment rule cuts across all of it: reviewers must be able to judge the contribution from the PDF alone. Supplements deepen; they never carry a load-bearing result.

The video figure

SIGCHI's video guide (sigchi.org/resources/guides-for-authors/videos/) sets the expectations this pack verifies: video figures illustrate key aspects of the work, run up to about five minutes, are archived in the DL, and every video needs a closed-caption file (SRT, SBV, or VTT). Craft rules that survive review:

• Show the interaction, not slides. Thirty seconds of real use beats two minutes of bullet points read aloud.
• Leave titles on screen long enough to read (the guide suggests up to ~10 seconds for video figures).
• Anonymize the audio track too: no narrator saying the lab's name, no institutional logos on walls or screens, no identifiable bystanders, and consent for every visible participant — including for eventual public archiving, not just review.
• Write the caption transcript yourself (or correct an auto-transcript line by line); auto-captions mangle technical vocabulary exactly where precision matters.
• Audio-describe or narrate what matters visually: the captions plus narration should let a listener who cannot see the screen follow the contribution.

# Video figure QA before PCS upload
ffprobe -v error -show_entries format=duration,size -of default=nw=1 videofigure.mp4
ffmpeg -i videofigure.mp4 -i videofigure.srt -c copy -c:s mov_text captioned.mp4
ffprobe -v error -select_streams s -show_entries stream=codec_name captioned.mp4  # captions present?
# Archive hygiene for the code/data supplement
zip -r supplement.zip supplement/ -x '*.git*' '*.DS_Store' '*node_modules*'
unzip -l supplement.zip | grep -Ei 'consent|irb|\.env|id_rsa|\.key' && echo "PURGE THESE"

Anonymization has more surface area here than in the paper

The PDF gets proofread; supplements leak. Recurring channels, all desk-reject grade (chi-submission): PDF/Office metadata inside appendix files, .git histories with author emails, notebook outputs showing home-directory paths with usernames, OSF or GitHub links registered to named accounts (use the platforms' anonymous-view mechanisms), app-store links for the studied prototype, and consent forms with letterhead. Sweep the exact files being uploaded, not the working copies.

Structure the archive for a tired reviewer

One README at the root, mapping files to paper sections; instruments in one folder; data dictionary beside the data; a one-command entry point for any code (chi-reproducibility holds the transparency ladder). A reviewer gives the archive five minutes — spend your effort on the first five minutes.

The video preview (after acceptance)

The ~30-second preview is optional but disproportionately valuable: it plays on YouTube and beside the DL record, and is how conference attendees choose sessions. One idea, one strong visual, captioned, titles readable in ~4 seconds per the guide. Produce it in February against the publication-ready deadline (2027-02-18), when the camera-ready is stable — not in deadline-week September (chi-camera-ready).

Cycle-volatile items

File-size caps and accepted formats for PCS uploads, whether the current cycle asks for specific supplement manifests, and any per-subcommittee expectations were 待核实 at check time — read the live "Guide to a Successful Submission" and video pages for the cycle before finalizing the package.

Output format

[Package] video figure ✓/✗ (captions ✓/✗) · appendix ✓/✗ · code/data ✓/✗ · README ✓/✗
[Self-containment] paper stands without supplements: yes/no
[Anonymity sweep] metadata · git history · links · audio track · footage consent — clean?
[Consent coverage] archival publication consent for all visible participants: yes/no
[Deferred to camera-ready] video preview · de-anonymized archives
[Blocking issue] <what stops upload today>