Doc2X batch image compression check — 2026-10-13

Two previously published self-authored PNGs are copied unchanged into separate
folders, each named figure.png. Chart:1600x1000,101,179bytes. Transparent shapes:
800x500,20,417bytes. These are not photographs or private documents.

One actual multi-file chooser selected both into the current public compression
tool. Three fresh compression runs used the SAME ORIGINAL INPUTS:
- JPEG Standard75%: chart69,414bytes; shapes12,177bytes.
- JPEG Low45%: chart48,645bytes; shapes8,948bytes.
- WebP Standard75%: chart39,752bytes; shapes10,094bytes.

Every actual ZIP contains exactly two different files, named compressed_figure
and compressed_figure (2) with the selected format suffix. Both image dimensions
remain unchanged. The second output is the transparent input, verified by its
content and800x500size, not inferred only from ZIP order or names.

JPEG removes transparency and produces opaque white outer margins. The native
WebP keeps the input's complete alpha channel byte-for-byte, including262,160
fully transparent pixels. Color pixels are compressed; this is not a lossless
image claim. White background and checkerboard are not interchangeable.

A separate actual single download of the second WebP is named
compressed_figure.webp, while the same bytes in the ZIP are named
compressed_figure (2).webp. A single file's name does not establish its batch
identity. Reopen files, compare dimensions/content, and retain originals.

Changing quality to45% cleared completed results and disabled Download all;
Start compression was clicked again before downloading the new ZIP. The tool
has no target-KB input. Using50,000bytes as an example limit, standardJPEG passes
only the shapes image; lowJPEG and standardWebP pass both examples. This does
not guarantee any batch will meet an arbitrary limit or retain adequate detail.

Four native download events observed:three ZIPs and one singleWebP. All native
outputs are unchanged. image-batch-inputs.zip and this outer proof ZIP were
assembled locally. The original folders inside input ZIP preserve duplicate
filenames without overwriting. Display comparison is locally composed from
native files; its checkerboard/labels are not part of downloaded image output.

No animation,EXIF,folder recursion,20-image maximum,unsupported formats,OCR,
upload to third-party image tools or product deployment was tested/performed.

中文：两张原始图片同名但内容不同。本包保留三次原生ZIP及一份单张WebP，
全部未经改写。ZIP中的第二张加(2)后缀，单张下载命名不同但字节一致。
JPEG透明区变为白色，WebP保留本例透明通道。质量设置改变后需重新生成。
50KB仅用于本样例逐张验收，不能据此保证任意批次或小字清晰度。
