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android自定義相機黑屏問題
對於一些手機，像HTC，當自定義Camera時，調用Camera.Parameters的parameters.setPreviewSize(width,height)方法時，如果width和height為奇數情況下，則會出現黑屏現象，解決辦法可參考SDK提供的ApiDemos中關於Camera的例子：
List<Size> sizes =parameters.getSupportedPreviewSizes();
Size optimalSize = getOptimalPreviewSize(sizes, w,h);
parameters.setPreviewSize(optimalSize.width, optimalSize.height);
同時，在HTC手機中，設置parameters.setPictureSize(width,height)屬性，也會導致黑屏，而在三星手機上則沒有問題。還有如果設置setPreviewSize屬性的寬高錯誤的話，拍出的照片也會存在失真等Bug，所以遇到適配問題時，最好的辦法就是不設置PreviewSize和PictureSize屬性。
getOptimalPreviewSize方法
private Size getOptimalPreviewSize(List<Size> sizes, int w, int h) {
final double ASPECT_TOLERANCE = 0.05;
double targetRatio = (double) w / h;
if (sizes == null)
return null;
Size optimalSize = null;
double minDiff = Double.MAX_VALUE;
int targetHeight = h;
// Try to find an size match aspect ratio and size
for (Size size : sizes) {
double ratio = (double) size.width / size.height;
if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE)
continue;
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
// Cannot find the one match the aspect ratio, ignore the requirement
if (optimalSize == null) {
minDiff = Double.MAX_VALUE;
for (Size size : sizes) {
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
}
return optimalSize;
}
最後更新：2017-04-03 18:52:03