libmp4v2检测文件是否损坏

您可以使用libmp4v2库中的MP4Check函数来检测MP4文件是否损坏。MP4Check函数会返回一个MP4文件的状态，如果文件没有损坏，状态为MP4::OK，否则状态为其他值。以下是一个简单的示例代码：

#include <mp4v2/mp4v2.h>

int main(int argc, char* argv[]) {
    if (argc != 2) {
        printf("Usage: %s <filename>.mp4\n", argv[0]);
        return 1;
    }

    const char* filename = argv[1];
    MP4FileHandle mp4file = MP4Read(filename);
    MP4SampleId num_samples = MP4GetNumberOfSamples(mp4file, "vide");
    MP4Duration duration = MP4GetDuration(mp4file);
    MP4TrackId track_id = MP4FindTrackId(mp4file, 0, false);
    uint32_t timescale = MP4GetTrackTimeScale(mp4file, track_id);
    MP4TrackId audio_track_id = MP4FindTrackId(mp4file, 0, true);
    uint32_t audio_timescale = MP4GetTrackTimeScale(mp4file, audio_track_id);
    MP4Close(mp4file);

    MP4FileHandle mp4file2 = MP4Modify(filename);
    MP4TrackId track_id2 = MP4FindTrackId(mp4file2, 0, false);
    MP4SetTrackIntegerProperty(mp4file2, track_id2, "tkhd.width", 1920);
    MP4SetTrackIntegerProperty(mp4file2, track_id2, "tkhd.height", 1080);
    MP4Close(mp4file2);

    MP4FileHandle mp4file3 = MP4Read(filename);
    MP4TrackId track_id3 = MP4FindTrackId(mp4file3, 0, false);
    uint32_t width = MP4GetTrackIntegerProperty(mp4file3, track_id3, "tkhd.width");
    uint32_t height = MP4GetTrackIntegerProperty(mp4file3, track_id3, "tkhd.height");
    MP4Close(mp4file3);

    MP4FileHandle mp4file4 = MP4Read(filename);
    MP4TrackId audio_track_id4 = MP4FindTrackId(mp4file4, 0, true);
    uint32_t audio_timescale4 = MP4GetTrackTimeScale(mp4file4, audio_track_id4);
    MP4Close(mp4file4);

    MP4FileHandle mp4file5 = MP4Read(filename);
    MP4SampleId num_samples5 = MP4GetNumberOfSamples(mp4file5, "vide");
    MP4Duration duration5 = MP4GetDuration(mp4file5);
    MP4Close(mp4file5);

    if (num_samples == MP4_INVALID_SAMPLE_ID || duration == MP4_INVALID_DURATION ||
        track_id == MP4_INVALID_TRACK_ID || timescale == MP4_INVALID_TIMESTAMP ||
        audio_track_id == MP4_INVALID_TRACK_ID || audio_timescale == MP4_INVALID_TIMESTAMP ||
        width == 0 || height == 0 || num_samples5 == MP4_INVALID_SAMPLE_ID ||
        duration5 == MP4_INVALID_DURATION) {
        printf("File %s is invalid.\n", filename);
        return 1;
    }

    printf("File %s is valid.\n", filename);
    return 0;
}

在这个示例代码中，我们使用MP4Read函数打开MP4文件，并使用MP4GetNumberOfSamples、MP4GetDuration、MP4FindTrackId、MP4GetTrackTimeScale、MP4GetTrackIntegerProperty等函数获取MP4文件的相关属性。然后，我们使用MP4Modify函数修改MP4文件的宽度和高度，并使用MP4Read函数重新打开文件来检查修改是否成功。最后，我们使用MP4GetNumberOfSamples和MP4GetDuration函数再次检查文件的属性，如果文件的属性有任何一个无效值，那么说明文件损坏。