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aiongg
3c64f9314e
When an operand failed to parse, the content parser went back to the byte after its start and tried again, so a run of n bytes that never reads as a number (a long run of '+', or digits ending in a letter) was read again from every one of its bytes: n^2/2 bytes from a tiny compressed stream. A failed number token longer than 64 bytes is now skipped whole; shorter ones still recover byte by byte.
pdfcraft-content
Layer L2: content streams (ISO 32000-2 §7.8.2, §8, §9).
let parsed = parse(&stream.decoded()?); // operators with operands and source spans
for op in &parsed.ops { if op.is("Tj") { /* … */ } }
let bytes = serialize_ops(&parsed.ops); // write back (inline images kept whole)
let m = Matrix::from_operands(&op.operands); // cm / Tm arithmetic, invert, bbox
The parser is tolerant (unreadable bytes are skipped and counted, never fatal) and never
panics. redact and (later) edit build their interpreters on it; the graphics-state tracker
and the Patch API of architecture §6 grow here.
Unfiltered inline images with built-in or Indexed colour spaces, and image masks, use their
sample layout (including per-row byte padding) to locate EI. This preserves pixel bytes
that look like the terminator. Filtered images and resource-defined colour spaces retain
the tolerant delimiter heuristic; damaged or truncated layouts fall back to it too.