diff options
Diffstat (limited to 'Lib/irix6/jpeg.py')
-rw-r--r-- | Lib/irix6/jpeg.py | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/Lib/irix6/jpeg.py b/Lib/irix6/jpeg.py new file mode 100644 index 0000000..85d6d83 --- /dev/null +++ b/Lib/irix6/jpeg.py @@ -0,0 +1,110 @@ +# Implement 'jpeg' interface using SGI's compression library + +# XXX Options 'smooth' and 'optimize' are ignored. + +# XXX It appears that compressing grayscale images doesn't work right; +# XXX the resulting file causes weirdness. + +error = 'jpeg.error' # Exception + +options = {'quality': 75, 'optimize': 0, 'smooth': 0, 'forcegray': 0} + +comp = None +decomp = None + +def compress(imgdata, width, height, bytesperpixel): + global comp + import cl, CL + if comp is None: comp = cl.OpenCompressor(CL.JPEG) + if bytesperpixel == 1: + format = CL.GRAYSCALE + elif bytesperpixel == 4: + format = CL.RGBX + if options['forcegray']: + iformat = CL.GRAYSCALE + else: + iformat = CL.YUV + # XXX How to support 'optimize'? + params = [CL.IMAGE_WIDTH, width, CL.IMAGE_HEIGHT, height, \ + CL.ORIGINAL_FORMAT, format, \ + CL.ORIENTATION, CL.BOTTOM_UP, \ + CL.QUALITY_FACTOR, options['quality'], \ + CL.INTERNAL_FORMAT, iformat, \ + ] + comp.SetParams(params) + jpegdata = comp.Compress(1, imgdata) + return jpegdata + +def decompress(jpegdata): + global decomp + import cl, CL + if decomp is None: decomp = cl.OpenDecompressor(CL.JPEG) + headersize = decomp.ReadHeader(jpegdata) + params = [CL.IMAGE_WIDTH, 0, CL.IMAGE_HEIGHT, 0, CL.INTERNAL_FORMAT, 0] + decomp.GetParams(params) + width, height, format = params[1], params[3], params[5] + if format == CL.GRAYSCALE or options['forcegray']: + format = CL.GRAYSCALE + bytesperpixel = 1 + else: + format = CL.RGBX + bytesperpixel = 4 + # XXX How to support 'smooth'? + params = [CL.ORIGINAL_FORMAT, format, \ + CL.ORIENTATION, CL.BOTTOM_UP, \ + CL.FRAME_BUFFER_SIZE, width*height*bytesperpixel] + decomp.SetParams(params) + imgdata = decomp.Decompress(1, jpegdata) + return imgdata, width, height, bytesperpixel + +def setoption(name, value): + if type(value) <> type(0): + raise TypeError, 'jpeg.setoption: numeric options only' + if name == 'forcegrey': + name = 'forcegray' + if not options.has_key(name): + raise KeyError, 'jpeg.setoption: unknown option name' + options[name] = int(value) + +def test(): + import sys + if sys.argv[1:2] == ['-g']: + del sys.argv[1] + setoption('forcegray', 1) + if not sys.argv[1:]: + sys.argv.append('/usr/local/images/data/jpg/asterix.jpg') + for file in sys.argv[1:]: + show(file) + +def show(file): + import gl, GL, DEVICE + jpegdata = open(file, 'r').read() + imgdata, width, height, bytesperpixel = decompress(jpegdata) + gl.foreground() + gl.prefsize(width, height) + win = gl.winopen(file) + if bytesperpixel == 1: + gl.cmode() + gl.pixmode(GL.PM_SIZE, 8) + gl.gconfig() + for i in range(256): + gl.mapcolor(i, i, i, i) + else: + gl.RGBmode() + gl.pixmode(GL.PM_SIZE, 32) + gl.gconfig() + gl.qdevice(DEVICE.REDRAW) + gl.qdevice(DEVICE.ESCKEY) + gl.qdevice(DEVICE.WINQUIT) + gl.qdevice(DEVICE.WINSHUT) + gl.lrectwrite(0, 0, width-1, height-1, imgdata) + while 1: + dev, val = gl.qread() + if dev in (DEVICE.ESCKEY, DEVICE.WINSHUT, DEVICE.WINQUIT): + break + if dev == DEVICE.REDRAW: + gl.lrectwrite(0, 0, width-1, height-1, imgdata) + gl.winclose(win) + # Now test the compression and write the result to a fixed filename + newjpegdata = compress(imgdata, width, height, bytesperpixel) + open('/tmp/j.jpg', 'w').write(newjpegdata) |