diff options
| -rw-r--r-- | AGENTS.md | 5 | ||||
| -rw-r--r-- | kitty-graphics.el | 140 |
2 files changed, 127 insertions, 18 deletions
@@ -265,7 +265,10 @@ Key design differences from images: - **Required**: Emacs >= 27.1, a supported terminal (Kitty/WezTerm/Ghostty for Kitty backend; foot/Konsole/xterm/mlterm/mintty for Sixel) -- **Required for Sixel**: ImageMagick (`magick`/`convert`) for encoding +- **Required for Sixel**: a Sixel encoder on PATH -- `img2sixel` + (libsixel, recommended) or ImageMagick (`magick`/`convert`). + Override via `kitty-gfx-sixel-encoder-program'; bound by + `kitty-gfx-sixel-encoder-timeout' (default 5s). - **Optional for Kitty**: ImageMagick for non-PNG formats and pixel-accurate sizing - **Optional for typst preview**: `typst` CLI on PATH (used by `kitty-gfx-typst-preview`) diff --git a/kitty-graphics.el b/kitty-graphics.el index 78eaebd..640454b 100644 --- a/kitty-graphics.el +++ b/kitty-graphics.el @@ -185,6 +185,28 @@ Default is `auto'." (const :tag "Sixel protocol" sixel)) :group 'kitty-graphics) +(defcustom kitty-gfx-sixel-encoder-program nil + "Program used to encode raster images to Sixel. +When nil, auto-detect: prefer `img2sixel' (libsixel), then +`magick' (ImageMagick 7), then `convert' (ImageMagick 6, deprecated). +When set to a string, use that program and treat it as `img2sixel'-style +unless the basename is `magick' or `convert'." + :type '(choice (const :tag "Auto-detect" nil) string) + :group 'kitty-graphics) + +(defcustom kitty-gfx-sixel-encoder-args nil + "Extra arguments passed to `kitty-gfx-sixel-encoder-program'. +These come before the per-invocation size flags and the input file." + :type '(repeat string) + :group 'kitty-graphics) + +(defcustom kitty-gfx-sixel-encoder-timeout 5.0 + "Maximum time in seconds to wait for a single Sixel encoder run. +When nil, wait indefinitely. Encoders that hang on a malformed image +will otherwise block Emacs." + :type '(choice (const :tag "No timeout" nil) number) + :group 'kitty-graphics) + (defcustom kitty-gfx-heading-scales '((1 . 2.0) (2 . 1.5) (3 . 1.2)) "Alist mapping org heading level to visual scale factor. Headings at levels not listed use scale 1.0 (normal size). @@ -587,35 +609,119 @@ OV is the overlay (unused by Kitty backend but part of the interface)." (hash (md5 key))) (expand-file-name (concat "kitty-gfx-sixel-" hash ".six") temporary-file-directory))) +(defun kitty-gfx--sixel-resolve-encoder () + "Resolve the Sixel encoder program. +Return a cons (KIND . ABS-PATH) where KIND is `img2sixel' or `imagemagick' +and ABS-PATH is the resolved executable path, or nil when no encoder +is available." + (let* ((user kitty-gfx-sixel-encoder-program) + (path (cond + (user (executable-find user)) + (t (or (executable-find "img2sixel") + (executable-find "magick") + (executable-find "convert")))))) + (when path + (let ((base (downcase (file-name-nondirectory path)))) + (cons (cond + ((string-prefix-p "img2sixel" base) 'img2sixel) + ((or (string-prefix-p "magick" base) + (string-prefix-p "convert" base)) 'imagemagick) + ;; User-specified non-standard binary: assume img2sixel-style + (t 'img2sixel)) + path))))) + +(defun kitty-gfx--sixel-run-encoder (program timeout dest-buffer args) + "Run PROGRAM with ARGS, writing stdout into DEST-BUFFER. +TIMEOUT, when a positive number, terminates the process after that many +seconds and signals an error. Errors include captured stderr. +Returns t on success, nil on failure (failures are logged, not signalled)." + (let* ((stderr-buf (generate-new-buffer " *kitty-gfx-sixel-stderr*")) + (process-connection-type nil) + (proc (make-process :name "kitty-gfx-sixel-encoder" + :buffer dest-buffer + :command (cons program args) + :coding 'binary + :connection-type 'pipe + :stderr stderr-buf + :noquery t)) + (timer (and (numberp timeout) + (> timeout 0) + (run-at-time + timeout nil + (lambda (p) + (when (process-live-p p) + (process-put p 'kitty-gfx-timed-out t) + (delete-process p))) + proc)))) + (set-process-sentinel proc #'ignore) + (unwind-protect + (progn + (while (process-live-p proc) + (accept-process-output proc 0.1)) + (let* ((timed-out (process-get proc 'kitty-gfx-timed-out)) + (exit (process-exit-status proc)) + (stderr (string-trim + (with-current-buffer stderr-buf (buffer-string))))) + (cond + (timed-out + (kitty-gfx--log + "sixel-encode: TIMEOUT after %.1fs (%s killed)" + (float timeout) program) + nil) + ((eq exit 0) t) + (t + (kitty-gfx--log "sixel-encode: %s exit=%s%s" + program exit + (if (string-empty-p stderr) + "" + (concat ": " stderr))) + nil)))) + (when timer (cancel-timer timer)) + (when (buffer-live-p stderr-buf) (kill-buffer stderr-buf))))) + (defun kitty-gfx--sixel-encode (png-file cols rows) "Encode PNG-FILE as Sixel data for COLS x ROWS cells. Returns Sixel data string or nil on failure. -Computes pixel dimensions from cell size." +Computes pixel dimensions from cell size. The encoder is selected via +`kitty-gfx-sixel-encoder-program' (auto-detected when nil) and bounded +by `kitty-gfx-sixel-encoder-timeout'." (let* ((cw (or kitty-gfx--cell-pixel-width 8)) (ch (or kitty-gfx--cell-pixel-height 16)) (pixel-w (* cols cw)) (pixel-h (* rows ch)) - (convert (or (executable-find "magick") (executable-find "convert")))) - (if (not convert) + (resolved (kitty-gfx--sixel-resolve-encoder))) + (if (not resolved) (progn - (kitty-gfx--log "sixel-encode: no ImageMagick, cannot encode") - (message "kitty-gfx: Sixel backend requires ImageMagick") + (kitty-gfx--log "sixel-encode: no encoder found (img2sixel/magick/convert)") + (message "kitty-gfx: Sixel backend requires img2sixel or ImageMagick") nil) - (when (string-suffix-p "convert" convert) - (kitty-gfx--log "sixel-encode: WARNING deprecated `convert' binary resolved: %s (use `magick' instead)" convert)) - (kitty-gfx--log "sixel-encode: %s -> %dx%d pixels via %s" - png-file pixel-w pixel-h convert) - (with-temp-buffer - (set-buffer-multibyte nil) - (let* ((args (list convert nil '(t nil) nil - png-file "-geometry" (format "%dx%d" pixel-w pixel-h) - "sixel:-")) - (exit-code (apply #'call-process args))) - (if (zerop exit-code) + (let* ((kind (car resolved)) + (path (cdr resolved)) + (base (file-name-nondirectory path)) + (args (pcase kind + ('img2sixel + (append kitty-gfx-sixel-encoder-args + (list "-w" (number-to-string pixel-w) + "-h" (number-to-string pixel-h)) + (list png-file))) + ('imagemagick + (append (list png-file) + kitty-gfx-sixel-encoder-args + (list "-geometry" + (format "%dx%d" pixel-w pixel-h)) + (list "sixel:-")))))) + (when (string-prefix-p "convert" (downcase base)) + (kitty-gfx--log "sixel-encode: WARNING deprecated `convert' resolved (%s); install `magick' or `img2sixel'" path)) + (kitty-gfx--log "sixel-encode: %s -> %dx%d pixels via %s (%s)" + png-file pixel-w pixel-h base kind) + (with-temp-buffer + (set-buffer-multibyte nil) + (if (kitty-gfx--sixel-run-encoder + path kitty-gfx-sixel-encoder-timeout + (current-buffer) args) (let ((data (buffer-string))) (kitty-gfx--log "sixel-encode: success (%d bytes)" (length data)) data) - (kitty-gfx--log "sixel-encode: FAILED exit=%d" exit-code) nil)))))) (defun kitty-gfx--sixel-prepare (file _image-id) |