ffmpeg-opengl-notes

LD_LIBRARY_PATH=../lib64/ ./glc-capture --start -v 3 --disable-audio --uncompressed=1M -z none -o /dev/stdout -l /dev/stderr etracer | LD_LIBRARY_PATH=../lib64/ ./glc-play /dev/stdin -t -v 3 -y 1 --uncompressed=1M -o /dev/stdout | ffmpeg -i /dev/stdin -f yuv4mpegpipe -pix_fmt yuv420p -vcodec libx264  -vprofile baseline -preset ultrafast -tune zerolatency -x264opts "intra-refresh:vbv-maxrate=5000:vbv-bufsize=200:slice-max-size=1500:sliced-threads" -threads auto -f yuv4mpegpipe -o /dev/stdout | ../../scripts/video/example

gcc -g -std=gnu99 -Wall -I/usr/include -L/usr/lib -L/usr/lib/x86_64-linux-gnu/ test.c aveasy.c -lglut -lGL -lGLU -lGLEW -lglfw  `pkg-config --cflags --libs libavcodec libavformat libavdevice libswscale` -o example

gl-texture-render

#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <math.h>

#include <GL/glew.h>
#include <GL/glfw.h>
#include <GL/glut.h>

#include "aveasy.h"

#define CAM_DESIRED_WIDTH 640
#define CAM_DESIRED_HEIGHT 480

AVEasyInputContext *camera_av;
char const *camera_path = "pipe:";

GLuint vbo=0;
GLuint pbo=0;
int use_pbo=0;
GLuint camera_texture=0

int open_camera(void)
{
    AVEasyInputContext *ctx;

    avcodec_register_all();
    avdevice_register_all();
    ctx = aveasy_input_open_v4l2(
        camera_path,
        CAM_DESIRED_WIDTH,
        CAM_DESIRED_HEIGHT,
        CODEC_ID_RAWVIDEO,
        PIX_FMT_BGR24 );
    camera_av = ctx;

    if(!ctx) {
        return 0;
    }
}

void update_camera(void)
{
    glPixelStorei( GL_UNPACK_SWAP_BYTES, GL_FALSE );
    glPixelStorei( GL_UNPACK_LSB_FIRST,  GL_TRUE  );
    glPixelStorei( GL_UNPACK_ROW_LENGTH, 0 );
    glPixelStorei( GL_UNPACK_SKIP_PIXELS, 0);
    glPixelStorei( GL_UNPACK_SKIP_ROWS, 0);
    glPixelStorei( GL_UNPACK_ALIGNMENT, 1);

    AVEasyInputContext *ctx = camera_av;
    void *buffer;

    if(!ctx)
        return;

    if( !( buffer = aveasy_input_read_frame(ctx) ) )
        return;

    glBindTexture(GL_TEXTURE_2D, camera_texture);
    glTexSubImage2D(
        GL_TEXTURE_2D,
        0,
        0,
        0,
        aveasy_input_width(ctx),
        aveasy_input_height(ctx),
        GL_BGR,
        GL_UNSIGNED_BYTE,
        buffer);
    glDrawArrays(GL_TRIANGLE_STRIP,0,4);
}


void close_cameras(void)
{
    aveasy_input_close(camera_av);
    camera_av=0;
}

int main(int argc, char **argv) {
	/* interleaved vertex array: T2F_V2F */ 
	static const GLfloat va[]={
		0.0f, 1.0f, -1.0f,  1.0f,
		0.0f, 0.0f, -1.0f, -1.0f,
		1.0f, 1.0f,  1.0f,  1.0f,
		1.0f, 0.0f,  1.0f, -1.0f};

    open_camera();

        glutInitWindowSize(320,240);
        glutInit(&argc, argv);

        glutInitDisplayMode(GLUT_RGBA|GLUT_DOUBLE);
        glutCreateWindow("TEST");
 
    // Initialize GLEW
    //glewExperimental=true; // Needed in core profile
    if (glewInit() != GLEW_OK) {
        fprintf(stderr, "Failed to initialize GLEW\n");
        return -1;
    }
 
    glfwSetWindowTitle( "Tutorial 01" );

    /* setup vbo */
    glGenBuffersARB(1, &vbo);
    glBindBufferARB(GL_ARRAY_BUFFER_ARB, vbo);
    glBufferDataARB(GL_ARRAY_BUFFER_ARB, sizeof(va), va, GL_STATIC_DRAW_ARB);

    glTexCoordPointer(2, GL_FLOAT, 4*sizeof(GLfloat), (char*)0);
    glVertexPointer(2, GL_FLOAT, 4*sizeof(GLfloat), ((char*)0)+2*sizeof(GLfloat));

    glEnableClientState(GL_VERTEX_ARRAY);
    glEnableClientState(GL_TEXTURE_COORD_ARRAY);

    glGenTextures(1, &camera_texture);

    /* OpenGL-2 or later is assumed; OpenGL-2 supports NPOT textures. */
    glBindTexture(GL_TEXTURE_2D, camera_texture);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexImage2D(
        GL_TEXTURE_2D,  
        0,
        GL_RGB, 
        aveasy_input_width(camera_av),
        aveasy_input_height(camera_av),
        0,
        GL_BGR,
        GL_UNSIGNED_BYTE,
        NULL );

    glEnable(GL_TEXTURE_2D);

    while(1) {
        update_camera();
        glutSwapBuffers();
    }
    close_camera();
}
offlinehacker@offlinehacker-laptop:~/tmp/scripts/video$