Showing stream video

[BrMisha]

Men, I really don't understand what is happening.
I installed msys2, and some packages for that, then i copied *c:\Qt\Qt5.14.2\Tools\mingw730_64* to *c:\msys64\mingw64*.
Then built libav (it is "small" version of FFmpeg) and got this files:

build\usr\local\bin\avcodec.lib
build\usr\local\bin\avcodec-58.dll
build\usr\local\bin\avconv.exe
build\usr\local\bin\avdevice.lib
build\usr\local\bin\avdevice-57.dll
build\usr\local\bin\avfilter.lib
build\usr\local\bin\avfilter-7.dll
build\usr\local\bin\avformat.lib
build\usr\local\bin\avformat-58.dll
build\usr\local\bin\avprobe.exe
build\usr\local\bin\avresample.lib
build\usr\local\bin\avresample-4.dll
build\usr\local\bin\avutil.lib
build\usr\local\bin\avutil-56.dll
build\usr\local\bin\swscale.lib
build\usr\local\bin\swscale-5.dll

build\usr\local\include\libavcodec\	<< here is *.h
build\usr\local\include\libavdevice\	<< here is *.h
build\usr\local\include\libavfilter\	<< here is *.h
build\usr\local\include\libavformat\	<< here is *.h
build\usr\local\include\libavresample\	<< here is *.h
build\usr\local\include\libavutil\	<< here is *.h
build\usr\local\include\libswscale\	<< here is *.h

build\usr\local\lib\pkgconfig\
build\usr\local\lib\avcodec-58.def
build\usr\local\lib\avdevice-57.def
build\usr\local\lib\avfilter-7.def
build\usr\local\lib\avformat-58.def
build\usr\local\lib\avresample-4.def
build\usr\local\lib\avutil-56.def
build\usr\local\lib\libavcodec.dll.a
build\usr\local\lib\libavdevice.dll.a
build\usr\local\lib\libavfilter.dll.a
build\usr\local\lib\libavformat.dll.a
build\usr\local\lib\libavresample.dll.a
build\usr\local\lib\libavutil.dll.a
build\usr\local\lib\libswscale.dll.a
build\usr\local\lib\swscale-5.def

*c:\Qt\Qt5.14.2\Tools\mingw730_64* was added to PATH. When I start, for example, avconv.exe, it works ok, so definitely libav was built with true mingw (which uses qt).
Next, i added to *.pro (using "Add library...") this:

win32: LIBS += -LF:/Musor/libav/build/usr/local/lib/ -llibavformat.dll
INCLUDEPATH += F:/Musor/libav/build/usr/local/include
DEPENDPATH += F:/Musor/libav/build/usr/local/include

main.c:

#include <libavformat/avformat.h>
int main(int argc, char *argv[]) {
	avformat_license();
	return 0;
}

After compilation i got:

C:/Qt/Qt5.14.2/Tools/mingw730_64/bin/mingw32-make -f Makefile.Debug
mingw32-make[1]: Entering directory 'D:/projects_test/qt/qt_test/build-qt_test-Desktop_Qt_5_14_2_MinGW_64_bit-Debug'
g++ -c -fno-keep-inline-dllexport -g -std=gnu++11 -Wall -Wextra -Wextra -fexceptions -mthreads -DUNICODE -D_UNICODE -DWIN32 -DMINGW_HAS_SECURE_API=1 -DQT_DEPRECATED_WARNINGS -DQT_QML_DEBUG -DQT_SERIALPORT_LIB -DQT_CORE_LIB -I..\qt_test -I. -IF:\Musor\libav\build\usr\local\include -IC:\Qt\Qt5.14.2\5.14.2\mingw73_64\include -IC:\Qt\Qt5.14.2\5.14.2\mingw73_64\include\QtSerialPort -IC:\Qt\Qt5.14.2\5.14.2\mingw73_64\include\QtCore -Idebug -IC:\Qt\Qt5.14.2\5.14.2\mingw73_64\mkspecs\win32-g++  -o debug\main.o ..\qt_test\main.cpp
..\qt_test\main.cpp: In function 'int main(int, char**)':
..\qt_test\main.cpp:4:14: warning: unused parameter 'argc' [-Wunused-parameter]
 int main(int argc, char *argv[])
              ^~~~
..\qt_test\main.cpp:4:31: warning: unused parameter 'argv' [-Wunused-parameter]
 int main(int argc, char *argv[])
                               ^
g++ -Wl,-subsystem,console -mthreads -o debug\qt_test.exe debug/main.o  -LF:\Musor\libav\build\usr\local\lib F:\Musor\libav\build\usr\local\lib\libavformat.dll.a C:\Qt\Qt5.14.2\5.14.2\mingw73_64\lib\libQt5SerialPort.a C:\Qt\Qt5.14.2\5.14.2\mingw73_64\lib\libQt5Core.a   
debug/main.o: In function `main':
D:\projects_test\qt\qt_test\build-qt_test-Desktop_Qt_5_14_2_MinGW_64_bit-Debug/../qt_test/main.cpp:6: undefined reference to `avformat_license()'
collect2.exe: error: ld returned 1 exit status
mingw32-make[1]: *** [Makefile.Debug:68: debug/qt_test.exe] Error 1
mingw32-make: *** [Makefile:45: debug] Error 2
mingw32-make[1]: Leaving directory 'D:/projects_test/qt/qt_test/build-qt_test-Desktop_Qt_5_14_2_MinGW_64_bit-Debug'
18:45:50: The process "C:\Qt\Qt5.14.2\Tools\mingw730_64\bin\mingw32-make.exe" exited with code 2.
Error while building/deploying project qt_test (kit: Desktop Qt 5.14.2 MinGW 64-bit)
When executing step "Make"

Whyyyyyyy?????
I have tried to change -llibavformat.dll to -lavformat, "-lavformat.dll" and "-lavformat" but i'm stil getting this error.

[SGaist]

Might be silly but try linking to all the ffmpeg libraries, just in case.

[Pablo J. Rogina]

@BrMisha said in Showing stream video:

build\usr\local\bin\avformat.lib
build\usr\local\bin\avformat-58.dll

not sure if that's the issue, but you're showing libraries built in build\usr\local\bin but you're using build\usr\local\lib in your .pro file:

win32: LIBS += -LF:/Musor/libav/build/usr/local/lib/ -llibavformat.dll

In addition, and not sure since it's a long time I don't use libraries in Windows, also keep in mind that you have different names between the .lib and .dll files (avformat.lib vs. avformat-58.dll)

[BrMisha]

@SGaist said in Showing stream video:

Might be silly but try linking to all the ffmpeg libraries, just in case.

I tried to add this LIBS += -llibavcodec.dll -llibavdevice.dll -llibavfilter.dll -llibavformat.dll -llibavresample.dll -llibavutil.dll -llibswscale.dll but i'm still getting errors.
By the way, if in cpp i'm adding

extern "C" {
	#include <libavformat/avformat.h>
}

then compils but falls in runtime on calling avformat_license()

[BrMisha]

@Pablo-J-Rogina "bin" contains *.exe and *dll. Libraries locates in "lib" folder

[SGaist]

Because you are likely missing the path to the folder where the dlls are in the PATH environment variable.

You can do that in the Run part of the Project panel.

[BrMisha]

But i did set *\libav\build\usr\local\bin\ to PATH before)))

[BrMisha]

Men, i have done it)))
So, we need to add bin to PATH, in .pro LIBS += -L/libav/build/usr/local/lib/ -llibavformat.dll.
I think, in a past it doesn't work because i didn't restart qt qreator after adding to PATH

[Pablo J. Rogina]

@BrMisha said in Showing stream video:

i have done it

so please don't forget to mark your post as solved.

[BrMisha]

So, how to get QImage from stream:

QUdpSocket *udpSocket;
QByteArray	buffer;

int read_packet(void *opaque, uint8_t *buf, int buf_size) {
	//auto	fil = static_cast<QUdpSocket*>(opaque);
	//QMutexLocker	l(&fil->mutex);
	//qDebug() << buf_size << fil->buffer.length();

	qDebug() << buf_size << buffer.length();

	if (buffer.isEmpty() && !udpSocket->hasPendingDatagrams()) udpSocket->waitForReadyRead();
	while (udpSocket->hasPendingDatagrams()) {
		if (buffer.length() > 1024*500) {
			buffer = buffer.right(1024*500);
			buffer.clear();
		}
		buffer.append(udpSocket->receiveDatagram().data());
	}

	buf_size = buffer.length() > buf_size ? buf_size : buffer.length();
	memcpy(buf, buffer.constData(), buf_size);
	buffer.remove(0, buf_size);

	return buf_size;
};

int MainWindow::start()
{
	QtConcurrent::run([this](){
		udpSocket = new QUdpSocket;
		udpSocket->bind(15004);

		AVFormatContext *fmt_ctx = nullptr;
		AVIOContext *avio_ctx = nullptr;
		uint8_t *buffer = nullptr, *avio_ctx_buffer = nullptr;
		size_t buffer_size = 0, avio_ctx_buffer_size = 4096;

		int ret = 0;
		fmt_ctx = avformat_alloc_context();
		Q_ASSERT(fmt_ctx);

		avio_ctx_buffer = reinterpret_cast<uint8_t*>(av_malloc(avio_ctx_buffer_size));
		Q_ASSERT(avio_ctx_buffer);
		avio_ctx = avio_alloc_context(avio_ctx_buffer, static_cast<int>(avio_ctx_buffer_size), 0, /*&bd*/udpSocket, &read_packet, nullptr, nullptr);
		Q_ASSERT(avio_ctx);

		fmt_ctx->pb = avio_ctx;
		ret = avformat_open_input(&fmt_ctx, nullptr, nullptr, nullptr);
		Q_ASSERT(ret >= 0);
		ret = avformat_find_stream_info(fmt_ctx, nullptr);
		Q_ASSERT(ret >= 0);

		AVStream	*video_stream = nullptr;
		for (uint i=0; i<fmt_ctx->nb_streams; ++i) {
			auto	st = fmt_ctx->streams[i];
			qDebug() << st->id << st->index << st->start_time << st->duration << st->codecpar->codec_type;
			if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) video_stream = st;
		}
		Q_ASSERT(video_stream);


		AVCodecParameters	*codecpar = video_stream->codecpar;
		AVCodec* codec = avcodec_find_decoder(codecpar->codec_id);
		AVCodecContext *codec_context = avcodec_alloc_context3(codec);
		int err = avcodec_open2(codec_context, codec, nullptr);
		Q_ASSERT(err>=0);
		qDebug() << codec->name << codec->id;
		qDebug() << codecpar->width << codecpar->height << codecpar->format << codec_context->pix_fmt;




		AVFrame	*frameRGB = av_frame_alloc();
		frameRGB->format = AV_PIX_FMT_RGB24;
		frameRGB->width = codecpar->width;
		frameRGB->height = codecpar->height;
		err = av_frame_get_buffer(frameRGB, 0);
		Q_ASSERT(err == 0);
		///
		SwsContext *imgConvertCtx = nullptr;

		AVFrame* frame = av_frame_alloc();
		AVPacket packet;

		while (av_read_frame(fmt_ctx, &packet) >= 0) {
			avcodec_send_packet(codec_context, &packet);
			err = avcodec_receive_frame(codec_context, frame);
			if (err == 0) {
				//qDebug() << frame->height << frame->width << codec_context->pix_fmt;

				imgConvertCtx = sws_getCachedContext(imgConvertCtx,
													 codecpar->width, codecpar->height, static_cast<AVPixelFormat>(codecpar->format),
													 frameRGB->width, frameRGB->height,
													 AV_PIX_FMT_RGB24, SWS_BICUBIC, nullptr, nullptr, nullptr);
				Q_ASSERT(imgConvertCtx);

				//conversion frame to frameRGB
				sws_scale(imgConvertCtx, frame->data, frame->linesize, 0, codec_context->height, frameRGB->data, frameRGB->linesize);

				//setting QImage from frameRGB
				QImage image(frameRGB->data[0],
						frameRGB->width,
						frameRGB->height,
						frameRGB->linesize[0],
						QImage::Format_RGB888);

				emit imageUpdated(image, clock());
			}

			av_frame_unref(frame);
			av_packet_unref(&packet);
		}
		if (imgConvertCtx) sws_freeContext(imgConvertCtx);





		//end:
		avformat_close_input(&fmt_ctx);
		/* note: the internal buffer could have changed, and be != avio_ctx_buffer */
		if (avio_ctx) {
			av_freep(&avio_ctx->buffer);
			av_freep(&avio_ctx);
		}
		av_file_unmap(buffer, buffer_size);
		if (ret < 0) {
			qWarning() << ret;
			return 1;
		}
		return 0;
	});
}

[Pablo J. Rogina]

@BrMisha said in Showing stream video:

So, how to get QImage from stream:

You've already marked the post as solved. Would you mind starting a new post then?
Given that this is slightly different (although related) topic...