def scale_image(data, width=60, height=80, compression_quality=70, as_png=False, preserve_aspect_ratio=True):
''' Scale an image, returning it as either JPEG or PNG data (bytestring).
Transparency is alpha blended with white when converting to JPEG. Is thread
safe and does not require a QApplication. '''
# We use Qt instead of ImageMagick here because ImageMagick seems to use
# some kind of memory pool, causing memory consumption to sky rocket.
if isinstance(data, QImage):
img = data
else:
img = QImage()
if not img.loadFromData(data):
raise ValueError('Could not load image for thumbnail generation')
if preserve_aspect_ratio:
scaled, nwidth, nheight = fit_image(img.width(), img.height(), width, height)
if scaled:
img = img.scaled(nwidth, nheight, Qt.KeepAspectRatio, Qt.SmoothTransformation)
else:
if img.width() != width or img.height() != height:
img = img.scaled(width, height, Qt.IgnoreAspectRatio, Qt.SmoothTransformation)
if not as_png and img.hasAlphaChannel():
nimg = QImage(img.size(), QImage.Format_RGB32)
nimg.fill(Qt.white)
p = QPainter(nimg)
p.drawImage(0, 0, img)
p.end()
img = nimg
ba = QByteArray()
buf = QBuffer(ba)
buf.open(QBuffer.WriteOnly)
fmt = 'PNG' if as_png else 'JPEG'
if not img.save(buf, fmt, quality=compression_quality):
raise ValueError('Failed to export thumbnail image to: ' + fmt)
return img.width(), img.height(), ba.data()
def add_image(self, img, cache_key):
ref = self.get_image(cache_key)
if ref is not None:
return ref
fmt = img.format()
image = QImage(img)
if (image.depth() == 1 and img.colorTable().size() == 2 and
img.colorTable().at(0) == QColor(Qt.black).rgba() and
img.colorTable().at(1) == QColor(Qt.white).rgba()):
if fmt == QImage.Format_MonoLSB:
image = image.convertToFormat(QImage.Format_Mono)
fmt = QImage.Format_Mono
else:
if (fmt != QImage.Format_RGB32 and fmt != QImage.Format_ARGB32):
image = image.convertToFormat(QImage.Format_ARGB32)
fmt = QImage.Format_ARGB32
w = image.width()
h = image.height()
d = image.depth()
if fmt == QImage.Format_Mono:
bytes_per_line = (w + 7) >> 3
data = image.constBits().asstring(bytes_per_line * h)
return self.write_image(data, w, h, d, cache_key=cache_key)
has_alpha = False
soft_mask = None
if fmt == QImage.Format_ARGB32:
tmask = image.constBits().asstring(4*w*h)[self.alpha_bit::4]
sdata = bytearray(tmask)
vals = set(sdata)
vals.discard(255) # discard opaque pixels
has_alpha = bool(vals)
if has_alpha:
# Blend image onto a white background as otherwise Qt will render
# transparent pixels as black
background = QImage(image.size(), QImage.Format_ARGB32_Premultiplied)
background.fill(Qt.white)
painter = QPainter(background)
painter.drawImage(0, 0, image)
painter.end()
image = background
ba = QByteArray()
buf = QBuffer(ba)
image.save(buf, 'jpeg', 94)
data = ba.data()
if has_alpha:
soft_mask = self.write_image(tmask, w, h, 8)
return self.write_image(data, w, h, 32, dct=True,
soft_mask=soft_mask, cache_key=cache_key)
def add_image(self, img, cache_key):
ref = self.get_image(cache_key)
if ref is not None:
return ref
fmt = img.format()
image = QImage(img)
if (image.depth() == 1 and img.colorTable().size() == 2 and
img.colorTable().at(0) == QColor(Qt.black).rgba() and
img.colorTable().at(1) == QColor(Qt.white).rgba()):
if fmt == QImage.Format_MonoLSB:
image = image.convertToFormat(QImage.Format_Mono)
fmt = QImage.Format_Mono
else:
if (fmt != QImage.Format_RGB32 and fmt != QImage.Format_ARGB32):
image = image.convertToFormat(QImage.Format_ARGB32)
fmt = QImage.Format_ARGB32
w = image.width()
h = image.height()
d = image.depth()
if fmt == QImage.Format_Mono:
bytes_per_line = (w + 7) >> 3
data = image.constBits().asstring(bytes_per_line * h)
return self.write_image(data, w, h, d, cache_key=cache_key)
has_alpha = False
soft_mask = None
if fmt == QImage.Format_ARGB32:
tmask = image.constBits().asstring(4*w*h)[self.alpha_bit::4]
sdata = bytearray(tmask)
vals = set(sdata)
vals.discard(255) # discard opaque pixels
has_alpha = bool(vals)
if has_alpha:
# Blend image onto a white background as otherwise Qt will render
# transparent pixels as black
background = QImage(image.size(), QImage.Format_ARGB32_Premultiplied)
background.fill(Qt.white)
painter = QPainter(background)
painter.drawImage(0, 0, image)
painter.end()
image = background
ba = QByteArray()
buf = QBuffer(ba)
image.save(buf, 'jpeg', 94)
data = bytes(ba.data())
if has_alpha:
soft_mask = self.write_image(tmask, w, h, 8)
return self.write_image(data, w, h, 32, dct=True,
soft_mask=soft_mask, cache_key=cache_key)
def scale_image(data,
width=60,
height=80,
compression_quality=70,
as_png=False,
preserve_aspect_ratio=True):
''' Scale an image, returning it as either JPEG or PNG data (bytestring).
Transparency is alpha blended with white when converting to JPEG. Is thread
safe and does not require a QApplication. '''
# We use Qt instead of ImageMagick here because ImageMagick seems to use
# some kind of memory pool, causing memory consumption to sky rocket.
if isinstance(data, QImage):
img = data
else:
img = QImage()
if not img.loadFromData(data):
raise ValueError('Could not load image for thumbnail generation')
if preserve_aspect_ratio:
scaled, nwidth, nheight = fit_image(img.width(), img.height(), width,
height)
if scaled:
img = img.scaled(nwidth, nheight, Qt.KeepAspectRatio,
Qt.SmoothTransformation)
else:
if img.width() != width or img.height() != height:
img = img.scaled(width, height, Qt.IgnoreAspectRatio,
Qt.SmoothTransformation)
if not as_png and img.hasAlphaChannel():
nimg = QImage(img.size(), QImage.Format_RGB32)
nimg.fill(Qt.white)
p = QPainter(nimg)
p.drawImage(0, 0, img)
p.end()
img = nimg
ba = QByteArray()
buf = QBuffer(ba)
buf.open(QBuffer.WriteOnly)
fmt = 'PNG' if as_png else 'JPEG'
if not img.save(buf, fmt, quality=compression_quality):
raise ValueError('Failed to export thumbnail image to: ' + fmt)
return img.width(), img.height(), ba.data()
def drawIconWithShadow(self,
icon,
rect,
painter,
iconMode,
radius=3,
color=QColor(0, 0, 0, 130),
offset=QPoint(1, -2)):
'''
@brief: Draw a cached pixmap with shadow
@param: icon QIcon
@param: rect QRect
@param: painter QPainter
@param: iconMode QIcon.Mode
@param: radius int
@param: color QColor
@param: offset QPoint
'''
cache = QPixmap()
pixmapName = 'icon %s %s %s' % (icon.cacheKey(), iconMode,
rect.height())
cache = QPixmapCache.find(pixmapName)
if not cache:
px = icon.pixmap(rect.size(), iconMode)
px.setDevicePixelRatio(gVar.app.devicePixelRatio())
cache = QPixmap(px.size() + QSize(radius * 2, radius * 2))
cache.setDevicePixelRatio(px.devicePixelRatioF())
cache.fill(Qt.transparent)
cachePainter = QPainter(cache)
# Draw shadow
tmp = QImage(px.size() + QSize(radius * 2, radius * 2 + 1),
QImage.Format_ARGB32_Premultiplied)
tmp.setDevicePixelRatio(px.devicePixelRatioF())
tmp.fill(Qt.transparent)
tmpPainter = QPainter(tmp)
tmpPainter.setCompositionMode(QPainter.CompositionMode_Source)
tmpPainter.drawPixmap(QPoint(radius, radius), px)
tmpPainter.end()
# blur the alpha channel
blurred = QImage(tmp.size(), QImage.Format_ARGB32_Premultiplied)
blurred.fill(Qt.transparent)
blurPainter = QPainter(blurred)
# TODO:
#qt_blurImage(blurPainter, tmp, radius, False, True)
blurPainter.end()
tmp = blurred
# blacken the image...
tmpPainter.begin(tmp)
tmpPainter.setCompositionMode(QPainter.CompositionMode_SourceIn)
tmpPainter.fillRect(tmp.rect(), color)
tmpPainter.end()
tmpPainter.begin(tmp)
tmpPainter.setCompositionMode(QPainter.CompositionMode_SourceIn)
tmpPainter.fillRect(tmp.rect(), color)
tmpPainter.end()
# draw the blurred drop shadow...
cachePainter.drawImage(
QRect(0, 0,
cache.rect().width() / cache.devicePixelRatioF(),
cache.rect().height() / cache.devicePixelRatioF()), tmp)
# Draw the actual pixmap...
cachePainter.drawPixmap(QPoint(radius, radius) + offset, px)
if self.usePixmapCache():
QPixmapCache.insert(pixmapName, cache)
sip.delete(cachePainter)
sip.delete(tmpPainter)
sip.delete(blurPainter)
targetRect = QRect(cache.rect())
targetRect.setWidth(cache.rect().width() / cache.devicePixelRatioF())
targetRect.setHeight(cache.rect().height() / cache.devicePixelRatioF())
targetRect.moveCenter(rect.center())
painter.drawPixmap(targetRect.topLeft() - offset, cache)
