The .qm file format is a compact binary format that provides extremely fast lookups for translations and that is used by Qt.
HEADERS         = funnydialog.h \
                  wackywidget.h
SOURCES         = funnydialog.cpp \
                  main.cpp \
                  wackywidget.cpp
FORMS           = fancybox.ui
TRANSLATIONS    = gnomovision_dk.ts \
                  gnomovision_fi.ts \
                  gnomovision_no.ts \
                  gnomovision_se.ts
When running lrelease on this project file, the Qt message files gnomovision_dk.qm, gnomovision_fi.qm, gnomovision_no.qm and gnomovision_se.qm will be generated from gnomovision_dk.ts, gnomovision_fi.ts, gnomovision_no.ts and gnomovision_se.ts, respectively.
Lrelease can also be invoked with a list of .ts files to convert:
lrelease gnomovision_*.ts