Hello, I have just discovered this repo. Is there any plan to support shared library(by calling .dll, .so, .dylib) and support for windows ? There was a WIP project that has not been updated over a year. I tried it but it has some audio skipping issues. Thank you for this work

Thanks for the great project. I used the tagged version but wanted to contribute so switched to master, where I had some trouble:

On master the project no longer works on darwin, but it does in 0.1.1. The change for a windows fix moved audio.go (and video.go) to a -windows and -linux suffix, but there is no -darwin so compile fails.

Hi! Thank you for this great project! I've tried your player code with your test mp4 and it works as intended. But when I try running it with any other mp4 video file I consistently get the error panic: buffered: len(pix) was 8294400 but must be 3686400. I noticed the factor between those two numbers is exactly 2.25. Any idea what the issue might be here? Thank you!

Getting errors when I go get reisen using go get github.com/zergon321/reisen

using brew install libav did not work for me, so tried building ffmpeg from source using brew install ffmpeg --build-from-source which installed all the library and header files, now i get all the following libraries in /usr/local/include and /usr/local/lib

• libavformat
• libavcodec
• libavutil
• libswresample
• libswscale

but I’m getting the following error after running go get github.com/zergon321/reisen ../../go/pkg/mod/github.com/zergon321/[email protected]/media.go:207:12: could not determine kind of name for C.av_bsf_receive_packet

../../go/pkg/mod/github.com/zergon321/[email protected]/media.go:199:12: could not determine kind of name for C.av_bsf_send_packet

I can confirm that all dependencies are install correctly. please whats happing and can anything be done to resolve this, thank you

Another question after spending more time with the video player example.

When playing longer videos I notice a slight drift between the video and the audio stream over time. This becomes even more pronounced when I add some extra image processing. I think I understand what the issue is: Essentially the video frame processing and the audio playing take place on their own go routines without any synchronization between them. So I guess the video processing could fall behind, while the audio processing keeps up? I understand that the player is just a very simple example, so this behavior is probably not surprising. Nevertheless any recommendation how to synchronize audio and video better would be great.

Also, just for my better understanding, I noticed that media.ReadPacket() will return audio and video packets at random for all open streams. Most of the time video and audio packets will alternate perfectly although every once in a while I see 2 video packets for 1 audio packet. What is the rational here in terms of stream synchronization?

I found a small issue with your player example code:

videoFPS, _ := media.Streams()[0].FrameRate()
spf := 1.0 / float64(videoFPS)
frameDuration, err := time.ParseDuration(fmt.Sprintf("%fs", spf)) 

You are ignoring the denominator here which is fine for your sample video but it should be considered for the general case.

But it gets more interesting yet. Some videos come with valid frame rate of 29.97. In this case the nominator will be 30000 and the denominator will be 1001 (which again is correct). However, if I play a video with that frame rate I observe the increasing drift between video and audio I reported in a previous issue. It gets better: If I manually force the frame rate to 30 instead of 29.97 the drift between audio and video is gone!

I observed the same for videos with 23.98 frame rate: There is a drift unless I force the player to play at 24 frames per second.

Currently, I'm working with mp4 snippets I download from youtube. Of course there is a possibility that the metadata is wrong in my mp4s but I don't think so. Other video players play those videos correctly - but then again those other players may do a better job syncing audio and video and ignore the possibly flawed frame rate data in my videos.

Anyways, just wanted to bring this to your attention and see if you have any insight why I have to "round up" 29.97 to 30 and 23.98 to 24. Thanks!

Hi! The following video crashes the player (with width and height constants adjusted to 1024 and 576) quite consistently:

https://user-images.githubusercontent.com/245089/197802318-9dbc7afd-8238-4983-8154-0f61bfb5b26d.mp4

It looks like a heap corruption (most likely a buffer overflow somewhere) and happens on Windows and Linux. When it does not crash, one can also see some corrupted pixels at the top of the screen. See screenshot:

The ffplayer utility plays the video without visible issues.

Linux crash message looks like this:

corrupted size vs. prev_size
Thread 8 "player" received signal SIGABRT, Aborted.

The call stack looks like this in GDB/Linux:

#0  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=0x6, no_tid=no_tid@entry=0x0) at ./nptl/pthread_kill.c:44
#1  0x00007ffff5e8989f in __pthread_kill_internal (signo=0x6, threadid=<optimized out>) at ./nptl/pthread_kill.c:78
#2  0x00007ffff5e3da52 in __GI_raise (sig=sig@entry=0x6) at ../sysdeps/posix/raise.c:26
#3  0x00007ffff5e28469 in __GI_abort () at ./stdlib/abort.c:79
#4  0x00007ffff5e7dc18 in __libc_message (action=action@entry=do_abort, fmt=fmt@entry=0x7ffff5fb4689 "%s\n") at ../sysdeps/posix/libc_fatal.c:155
#5  0x00007ffff5e9355a in malloc_printerr (str=str@entry=0x7ffff5fb2161 "corrupted size vs. prev_size") at ./malloc/malloc.c:5531
#6  0x00007ffff5e93eb6 in unlink_chunk (p=<optimized out>, av=0x7fffa4000020) at ./malloc/malloc.c:1626
#7  0x00007ffff5e94040 in malloc_consolidate (av=av@entry=0x7fffa4000020) at ./malloc/malloc.c:4663
#8  0x00007ffff5e95d88 in _int_malloc (av=av@entry=0x7fffa4000020, bytes=bytes@entry=0xa10) at ./malloc/malloc.c:3848
#9  0x00007ffff5e96e9f in _int_memalign (av=av@entry=0x7fffa4000020, alignment=alignment@entry=0x40, bytes=bytes@entry=0x9a7) at ./malloc/malloc.c:4851
#10 0x00007ffff5e9752a in _mid_memalign (alignment=alignment@entry=0x40, bytes=bytes@entry=0x9a7, address=<optimized out>) at ./malloc/malloc.c:3453
#11 0x00007ffff5e98a2f in __posix_memalign (size=0x9a7, alignment=0x40, memptr=0x7fffbe1c03b0) at ./malloc/malloc.c:5557
#12 __posix_memalign (memptr=0x7fffbe1c03b0, alignment=0x40, size=0x9a7) at ./malloc/malloc.c:5541
#13 0x00007ffff7e05aad in av_malloc () at /lib/x86_64-linux-gnu/libavutil.so.57
#14 0x00007ffff7dd2d15 in av_buffer_alloc () at /lib/x86_64-linux-gnu/libavutil.so.57
#15 0x00007ffff7dd2d8e in av_buffer_allocz () at /lib/x86_64-linux-gnu/libavutil.so.57
#16 0x00007ffff7dd3656 in av_buffer_pool_get () at /lib/x86_64-linux-gnu/libavutil.so.57
#17 0x00007ffff6795da4 in  () at /lib/x86_64-linux-gnu/libavcodec.so.59
#18 0x00007ffff679a148 in  () at /lib/x86_64-linux-gnu/libavcodec.so.59
#19 0x00007ffff679eca5 in  () at /lib/x86_64-linux-gnu/libavcodec.so.59
#20 0x00007ffff667e841 in  () at /lib/x86_64-linux-gnu/libavcodec.so.59
#21 0x00007ffff667f4c0 in avcodec_send_packet () at /lib/x86_64-linux-gnu/libavcodec.so.59
#22 0x0000000000573c3b in _cgo_c6952d519846_Cfunc_avcodec_send_packet (v=0xc000233628) at /tmp/go-build/cgo-gcc-prolog:276
#23 0x00000000004722a4 in runtime.asmcgocall () at /usr/lib/go-1.19/src/runtime/asm_amd64.s:844
#24 0x0000000000000001 in  ()
#25 0x0000000000443900 in runtime.fatal at /usr/lib/go-1.19/src/runtime/panic.go:1062
#26 0x0000000000470429 in runtime.systemstack () at /usr/lib/go-1.19/src/runtime/asm_amd64.s:492
#27 0x0000000000000000 in  ()

nice work , simple and clean . i have just read your article on Medium , learned your findings . i used to play with this Go Media Framework . it seems a full-featured binding , but not very active . wanna take a look ?

Hi! I tried to make the sample player more useful (can play a file from command line), use less memory, and the code is also a bit safer. If any of these changes doesn’t suit you, I’m happy to fix or submit another PR restricted to what you’d like to keep.

Thanks for providing this library, by the way. It is quite straightforward and does the job very nicely.

tried multiple files, same error.

go run main.go
Duration: 2m30.102176s
Format name: mov,mp4,m4a,3gp,3g2,mj2
Format long name: QuickTime / MOV
MIME type: 
Number of streams: 2

panic: time: invalid duration "NaNs"

goroutine 1 [running]:
main.handleError(...)
        <omitted>/main.go:142
main.main()
        <omitted>/main.go:28 +0x11bf
exit status 2
------
Duration: 4m0.140416s
Format name: matroska,webm
Format long name: Matroska / WebM
MIME type: audio/webm,audio/x-matroska,video/webm,video/x-matroska
Number of streams: 2

panic: time: invalid duration "NaNs"

goroutine 1 [running]:
main.handleError(...)
       <omitted>/main.go:142
main.main()
        <omitted>/main.go:28 +0x11bf
exit status 2

I ran libav as the README noted:

🍺  /usr/local/Cellar/libav/12.3_8: 15 files, 32.4MB
==> Running `brew cleanup libav`...
Disable this behaviour by setting HOMEBREW_NO_INSTALL_CLEANUP.
Hide these hints with HOMEBREW_NO_ENV_HINTS (see `man brew`).
==> No outdated dependents to upgrade!
==> Checking for dependents of upgraded formulae...
Disable this behaviour by setting HOMEBREW_NO_INSTALLED_DEPENDENTS_CHECK.
Hide these hints with HOMEBREW_NO_ENV_HINTS (see `man brew`).
==> Reinstalling 1 dependent with broken linkage from source:
libav
Warning: libav has been deprecated because it is not maintained upstream!