diff options
Diffstat (limited to 'src/lib')
| -rw-r--r-- | src/lib/album-photo-select.source.sh | 55 |
1 files changed, 33 insertions, 22 deletions
diff --git a/src/lib/album-photo-select.source.sh b/src/lib/album-photo-select.source.sh index 283e17b..cae4f9f 100644 --- a/src/lib/album-photo-select.source.sh +++ b/src/lib/album-photo-select.source.sh @@ -12,7 +12,8 @@ # Main album display order, in precedence order (task 8v0): # 1. CHRONOLOGICAL_ORDER=yes -> chronological_photo_files (EXIF date taken, -# ascending, falling back to mtime for photos without one). +# ascending, falling back to filename order for photos without a usable +# one). # 2. otherwise -> the historical maybe_shuffle path (seeded/random SHUFFLE, or # plain filename sort when SHUFFLE=no). # CHRONOLOGICAL_ORDER therefore takes precedence over SHUFFLE when both are @@ -36,6 +37,16 @@ album_photo_files() { | maybe_shuffle } +# Digital cameras were not commercially available before the 1990s, and a +# long tail of camera bodies -- including the Fujifilm X100V that motivated +# this constant -- silently default their clock to "2000-01-01" (or similar) +# once its battery dies, then stamp every EXIF timestamp with that bogus date +# instead of omitting it. An EXIF year below this is therefore treated as +# unusable rather than real, so a whole clock-reset camera roll does not sort +# to the very front of an otherwise correctly-dated album (see +# chronological_sort_key_for_photo). +readonly CHRONOLOGICAL_MIN_PLAUSIBLE_YEAR=2001 + # Build the sort key chronological_photo_files uses to order one photo: a # tab-separated "<group>\t<time>\t<photo>" line consumed by a plain lexicographic # sort (see chronological_photo_files). EXIF reads always target the INCOMING_DIR @@ -43,28 +54,27 @@ album_photo_files() { # resized DIST_DIR copy, so ordering and tooltip/details agree about a photo's # taken time and both share the same identify cache entry. # -# group 0 when photo_date_taken (album-metadata.source.sh) found a real EXIF -# date, 1 otherwise. Group 0 always sorts before group 1, so photos -# with a genuine timestamp are never displaced by an approximate -# fallback for photos that lack one. +# group 0 when photo_date_taken (album-metadata.source.sh) found a real, +# plausible (CHRONOLOGICAL_MIN_PLAUSIBLE_YEAR or later) EXIF date, 1 +# otherwise. Group 0 always sorts before group 1, so photos with a +# genuine timestamp are never displaced by an approximate fallback. # time the EXIF date normalized from "YYYY:MM:DD HH:MM:SS" to a 14-digit # "YYYYMMDDHHMMSS" string (colons/space just stripped -- the calendar # substrings are untouched, so this stays safe even though the EXIF # string is not `date -d`-parseable, see docs/stats-exif-audit.md) for -# group 0, or the INCOMING_DIR file's mtime (compat.source.sh $STAT, -# zero-padded so it sorts lexicographically) for group 1. Fixed width -# within each group keeps a plain sort numerically correct. -# photo final tiebreaker so photos sharing a timestamp (e.g. burst shots) or -# missing both an EXIF date and a readable mtime still sort in a -# stable, reproducible order across regenerations of the same -# incoming set. +# group 0, or the photo's own filename for group 1 (see the fallback +# comment below for why filename, not mtime). Fixed width within +# group 0 keeps a plain sort numerically correct. +# photo final tiebreaker so photos sharing a timestamp (e.g. burst shots) +# still sort in a stable, reproducible order across regenerations of +# the same incoming set. chronological_sort_key_for_photo() { local -r photo="$1"; shift local date_time - local mtime date_time=$(photo_date_taken "$photo" "$INCOMING_DIR/$photo") - if [[ "$date_time" =~ ^([0-9]{4}):([0-9]{2}):([0-9]{2})\ ([0-9]{2}):([0-9]{2}):([0-9]{2})$ ]]; then + if [[ "$date_time" =~ ^([0-9]{4}):([0-9]{2}):([0-9]{2})\ ([0-9]{2}):([0-9]{2}):([0-9]{2})$ ]] \ + && ((10#${BASH_REMATCH[1]} >= CHRONOLOGICAL_MIN_PLAUSIBLE_YEAR)); then printf '0\t%s%s%s%s%s%s\t%s\n' \ "${BASH_REMATCH[1]}" "${BASH_REMATCH[2]}" "${BASH_REMATCH[3]}" \ "${BASH_REMATCH[4]}" "${BASH_REMATCH[5]}" "${BASH_REMATCH[6]}" \ @@ -72,14 +82,15 @@ chronological_sort_key_for_photo() { return fi - # No usable EXIF date-taken (missing tag or a malformed value): fall back to - # the source file's mtime so ordering still reflects "roughly when this - # photo appeared" rather than an arbitrary readdir order, and stays fully - # deterministic across runs. A missing/unreadable source file (should not - # happen; INCOMING_DIR is validated before generation) reads as mtime 0 so - # this never aborts the render. - mtime=$("$STAT" -c '%Y' "$INCOMING_DIR/$photo" 2>/dev/null) || mtime=0 - printf '1\t%020d\t%s\n' "$mtime" "$photo" + # No usable EXIF date-taken (tag missing, malformed, or an implausible + # clock-reset default): fall back to plain filename order rather than + # source mtime. mtime looked like a reasonable fallback but is not a + # reliable proxy for capture order in practice -- copying/rsyncing an + # incoming directory commonly touches every file's mtime to the transfer + # time, unrelated to when it was actually shot -- whereas sequential + # camera filenames (e.g. Fujifilm's DSCFnnnn shutter-count naming) track + # real shooting order even across a clock reset. + printf '1\t%s\t%s\n' "$photo" "$photo" } # Chronological ordering for CHRONOLOGICAL_ORDER=yes: every photo in |