avcodec_alloc_context3 and avcodec_alloc_frame causes app to exit on Android 3.2

[pawg]

I am trying to decode H264 video on Samsung Galaxy Tab 10.1 using Android 3.2, kernel version 2.6.36.3. I am using FFmpeg software decoder. When I try to allocate context or frame using avcodec_alloc_context3 or avcodec_alloc_frame, my app freezes and after about 5 seconds exits without any error or log captured on Logcat.

Code which fails:

AVCodec* myCodec;
AVCodecContext* myContext;
AVFrame* myFrame;

myCodec = avcodec_find_decoder(CODEC_ID_H264);
myContext = avcodec_alloc_context3(myCodec);
myFrame = avcodec_alloc_frame();

[cehoyos]

The code you provide does not look as if it would compile, and please add backtrace if FFmpeg really freezes.

[pawg]

My code compiles fine using latest android ndk. Not sure what you mean by backtrace, but I added output from android system log. I may add that on android 2.x there are no problems with my app.

[cehoyos]

Replying to pawg:

My code compiles fine using latest android ndk.

Which code? You only posted a small part that will not compile.

Not sure what you mean by backtrace

Please see http://ffmpeg.org/bugreports.html

[pawg]

My codec initialization function is the following:

/*
AVCodec* myCodec;
AVCodecContext* myContext;
AVFrame* myFrame;
**These variables are defined at class level - put here only for information*/

init(){

avcodec_init();
avcodec_register_all();
myCodec = NULL;

myCodec = avcodec_find_decoder(CODEC_ID_H264);
if (!myCodec) {

log.error("codec CODEC_ID_H264 not found");
return;

}

/*this function causes the application to exit, the same goes for avcodec_alloc_frame if I comment this line*/
myContext = avcodec_alloc_context3(myCodec);

if (myCodec->capabilities & CODEC_CAP_TRUNCATED)

myContext->flags |= CODEC_FLAG_TRUNCATED;

myContext->flags2 |= (CODEC_FLAG2_CHUNKS | CODEC_FLAG_TRUNCATED);

if (avcodec_open(myContext, myCodec) < 0) {

log.error("Could not open codec");
return;

}
myFrame = avcodec_alloc_frame();
log.information("initialized decoder");

}

[cehoyos]

I still believe that a C (or C++) program that has "AVCodec* myCodec;" as first line will not compile. Don't you think so?

Please consider providing gdb output, it will show where the problem you see occurs.

[pawg]

I made an update to my source code - the variables were only defined as reference and the function is part of a bigger class. The provided output.txt from dump gives info that a possible problem is with av_opt_set_defaults2 function.

[michael]

output.txt says SIGILL which very likely means you used the wrong compiler options to compile some of the code.

[cehoyos]

Please reopen if you can at least provide gdb output, see http://ffmpeg.org/bugreports.html

[pawg]

Ticket can be left as closed with "no issue" status - ndk compiler needed to have additional flags for Tegra 2 cpu