various codecs support (e.g H.264, HEVC, VP8, VP9, MJPEG, ...)

- extends nhve_hw_config with encoder field
- following similar extension of HVE

Related to #1

examples/nhve_stream_h264.c

@@ -23,6 +23,7 @@ const int HEIGHT=360;
 const int FRAMERATE=30;
 int SECONDS=10;
 const char *DEVICE; //NULL for default or device e.g. "/dev/dri/renderD128"
+const char *ENCODER=NULL;//NULL for default (h264_vaapi) or FFmpeg encoder e.g. "hevc_vaapi", ...
 const char *PIXEL_FORMAT="nv12"; //NULL / "" for default (NV12) or pixel format e.g. "rgb0"
 const int PROFILE=FF_PROFILE_H264_HIGH; //or FF_PROFILE_H264_MAIN, FF_PROFILE_H264_CONSTRAINED_BASELINE, ...
 const int BFRAMES=0; //max_b_frames, set to 0 to minimize latency, non-zero to minimize size
@@ -43,7 +44,7 @@ int main(int argc, char* argv[])
 
 	//prepare library data
 	struct nhve_net_config net_config = {IP, PORT};
-	struct nhve_hw_config hw_config = {WIDTH, HEIGHT, FRAMERATE, DEVICE, PIXEL_FORMAT, PROFILE, BFRAMES, BITRATE};
+	struct nhve_hw_config hw_config = {WIDTH, HEIGHT, FRAMERATE, DEVICE, ENCODER, PIXEL_FORMAT, PROFILE, BFRAMES, BITRATE};
 	struct nhve *streamer;
 
 	//initialize library with nhve_init

nhve.c

@@ -1,7 +1,7 @@
 /*
  * NHVE Network Hardware Video Encoder C library implementation
  *
- * Copyright 2019 (C) Bartosz Meglicki <[email protected]>
+ * Copyright 2019-2020 (C) Bartosz Meglicki <[email protected]>
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -31,7 +31,7 @@ struct nhve *nhve_init(const struct nhve_net_config *net_config,const struct nhv
 	struct nhve *n, zero_nhve = {0};
 	struct mlsp_config mlsp_cfg = {net_config->ip, net_config->port, 0};
 	struct hve_config hve_cfg = {hw_config->width, hw_config->height, hw_config->framerate, hw_config->device,
-		hw_config->pixel_format, hw_config->profile, hw_config->max_b_frames, hw_config->bit_rate};
+		hw_config->encoder, hw_config->pixel_format, hw_config->profile, hw_config->max_b_frames, hw_config->bit_rate};
 
 	if( ( n = (struct nhve*)malloc(sizeof(struct nhve))) == NULL )
 	{

nhve.h

@@ -1,7 +1,7 @@
 /*
  * NHVE Network Hardware Video Encoder C library header
  *
- * Copyright 2019 (C) Bartosz Meglicki <[email protected]>
+ * Copyright 2019-2020 (C) Bartosz Meglicki <[email protected]>
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -28,6 +28,7 @@ struct nhve_hw_config
 	int height; //!< height of the encoded frames
 	int framerate; //!< framerate of the encoded video
 	const char *device; //!< NULL / "" or device, e.g. "/dev/dri/renderD128"
+	const char *encoder; //!< NULL / "" or encoder, e.g. "h264_vaapi"
 	const char *pixel_format; //!< NULL / "" for NV12 or format, e.g. "rgb0", "bgr0", "nv12", "yuv420p"
 	int profile; //!< 0 to guess from input or profile e.g. FF_PROFILE_H264_MAIN, FF_PROFILE_H264_HIGH
 	int max_b_frames; //!< maximum number of B-frames between non-B-frames (disable if you need low latency)