X264编码H264视频

通过V4l2 接口获取摄像头YUV数据，再将该数据使用X264编码成h264视频。详细内容请见博客http://blog.csdn.net/li_wen01/article/details/53572642

/*=============================================================================
#     FileName: h264encoder.c
#         Desc: this program aim to get image from USB camera
#               used the V4L2 interface.
#       Author: Licaibiao
#      Version: 
#   LastChange: 2016-12-11 
#      History:

=============================================================================*/
#include 
#include 
#include 
#include “./include/h264encoder.h“

void compress_begin（Encoder *en int width int height） {
	en->param = （x264_param_t *） malloc（sizeof（x264_param_t））;
	en->picture = （x264_picture_t *） malloc（sizeof（x264_picture_t））;
	x264_param_default（en->param）; //set default param
	//en->param->rc.i_rc_method = X264_RC_CQP;
	// en->param->i_log_level = X264_LOG_NONE;

	 en->param->i_threads  = X264_SYNC_LOOKAHEAD_AUTO;

	en->param->i_width = width; //set frame width
	en->param->i_height = height; //set frame height

	en->param->i_frame_total = 0;

	en->param->i_keyint_max = 10;
	en->param->rc.i_lookahead = 0; 
	en->param->i_bframe = 5; 

	en->param->b_open_gop = 0;
	en->param->i_bframe_pyramid = 0;
	en->param->i_bframe_adaptive = X264_B_ADAPT_TRELLIS;

	en->param->rc.i_bitrate = 1024 * 10;//rate 10 kbps
	en->param->i_fps_num = 25; 
	en->param->i_fps_den = 1;
	x264_param_apply_profile（en->param x264_profile_names[0]）; 

	if （（en->handle = x264_encoder_open（en->param）） == 0） {
		return;
	}
	/* Create a new pic */
	x264_picture_alloc（en->picture X264_CSP_I420 en->param->i_width
			en->param->i_height）;
	en->picture->img.i_csp = X264_CSP_I420;
	en->picture->img.i_plane = 3;
}

int compress_frame（Encoder *en int type uint8_t *in uint8_t *out） {
	x264_picture_t pic_out;
	int nNal = -1;
	int result = 0;
	int i = 0;
	uint8_t *p_out = out;

	char *y = en->picture->img.plane[0];   
	char *u = en->picture->img.plane[1];   
	char *v = en->picture->img.plane[2];   

	//yuv420_length = 1.5 * en->param->i_width * en->param->i_height
	//int length =  en->param->i_width * en->param->i_height;
	//y = 640*480 ; U = 640*480*0.25 V = 640*480*0.25; 
	memcpy（yin307200）;
	memcpy（uin+30720076800）;
	memcpy（vin+38400076800）;
	
	switch （type） {
	case 0:
		en->picture->i_type = X264_TYPE_P;
		break;
	case 1:
		en->picture->i_type = X264_TYPE_IDR;
		break;
	case 2:
		en->picture->i_type = X264_TYPE_I;
		break;
	default:
		en->picture->i_type = X264_TYPE_AUTO;
		break;
	}

	if （x264_encoder_encode（en->handle &（en->nal） &nNal en->picture
			&pic_out） < 0） {
		return -1;
	}

	for （i = 0; i < nNal; i++） {
		memcpy（p_out en->nal[i].p_payload en->nal[i].i_payload）;   
		p_out += en->nal[i].i_payload;								 
		result += en->nal[i].i_payload;
	}

	return result;
}

void compress_end（Encoder *en） {
	if （en->picture） {
		x264_picture_clean（en->picture）;
		free（en->picture）;
		en->picture = 0;
	}
	if （en->param） {
		free（en->param）;
		en->param = 0;
	}
	if （en->handle） {
		x264_encoder_close（en->handle）;
	}
	//free（en）;
}