某个 mp4 生成缩略图失败

[nanpuyue]

video.mp4

下载这个 mp4，替换 tests/assets/vids/bear.mp4，然后执行 thumbnail 测试：

wget https://user-images.githubusercontent.com/1524609/131678290-c6b90aee-d018-4078-99b4-45cc410bd67b.mp4 -O video.mp4
cp video.mp4 tests/assets/vids/bear.mp4
cargo test --test thumbnail

会得到如下错误：

    Finished test [unoptimized + debuginfo] target(s) in 0.04s
     Running tests/thumbnail.rs (target/debug/deps/thumbnail-fb8cd98fade3377b)

running 1 test
test thumbnail_test ... FAILED

failures:

---- thumbnail_test stdout ----
thread 'thumbnail_test' panicked at 'called `Result::unwrap()` on an `Err` value: Cannnot find video cover packet', tests/thumbnail.rs:132:6
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace


failures:
    thumbnail_test

test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s

error: test failed, to rerun pass '--test thumbnail'

[nanpuyue]

但是直接使用 ffmpeg 命令是可以的：

ffmpeg -i video.mp4 -frames:v 1 1.png

[nanpuyue]

糊了一个 telegram bot 用来设置群头像，之前用的 opencv，想用 ffmpeg 代替 opencv，糊好了发现有个文件不能生成图片，这也太惨了。
https://github.com/nanpuyue/avatar-bot

[ldm0]

惨，原因是当时写测试的时候没有想到超短视频。

改成这样这样就可以了。拿不到新packet的时候向解码 context 发送一下None 用以 flush，那个图片就能出来了。

[nanpuyue]

Wow，谢谢！

[nanpuyue]

顺便在隔壁 pr 提交了修复。
#65

[ldm0]

Closed by #65