QTMovie 未写入文件

Question

我正试图将这些图像添加到QTMovie中，但文件从未出现。我认为这与属性或addImage: 有关

NSTimeInterval t;
QTGetTimeInterval(frameInterval, &t);
NSLog(@"%f", t); // outputs 0.0333333

// --- initializes the movie ---
NSError *error = nil;
NSDictionary *at = [NSDictionary dictionaryWithObjectsAndKeys:
                    [NSNumber numberWithBool:YES], QTMovieEditableAttribute,
                    nil];
QTMovie *tst = [QTMovie movieWithAttributes:at error:&error];
if (error) {
    NSLog(@"%@", [error localizedDescription]); // outputs (null)
}

// --- initializes the images ---
NSImage *i1 = [[NSImage alloc] 
               initWithContentsOfFile:@"~/agimgs/1.tiff"];
NSImage *i2 = [[NSImage alloc] 
               initWithContentsOfFile:@"~/agimgs/110.tiff"];
NSImage *i3 = [[NSImage alloc] 
               initWithContentsOfFile:@"~/agimgs/130.tiff"];
// --- adds the images ---
for (int j=0; j<50; j++) {
    [tst addImage:i1 forDuration:frameInterval withAttributes:dict];
    [tst addImage:i2 forDuration:frameInterval withAttributes:dict];
    [tst addImage:i3 forDuration:frameInterval withAttributes:dict];
}
// --- (supposed to) output the movie ---
dict = [NSDictionary dictionaryWithObjectsAndKeys:
        [NSNumber numberWithBool:YES], QTMovieExport,
        nil];
BOOL worked = [tst writeToFile:@"/Users/nathanmswan/aaaa.mov" withAttributes:dict error:&error];
if (!worked) {
    NSLog(@"%@", [error localizedDescription]); // outputs nothing
}
NSLog(@"done with aaaa.mov");

Answer 1

您可以直接将电影写入类似的文件

NSString *tempName =  [NSString stringWithFormat:@"/Users/nathanmswan/aaaa.mov"];
tst = [[QTMovie alloc] initToWritableFile:tempName error:NULL];

添加一帧之后

[tst updateMovieFile];

这将创建文件，然后将所有内容写入文件，然后保存。不需要writeToFile:。但是，addImage:方法中使用的"dict"在使用之前似乎没有初始化。。。它应该参考addImage的编解码器：例如，

dict = [NSDictionary dictionaryWithObjectsAndKeys:@"mp4v",
           QTAddImageCodecType,
           [NSNumber numberWithLong:codecHighQuality],
           QTAddImageCodecQuality,
           nil];