我正在尝试在Android上创建一个 360视频领域(就像纸板一样)。我通过在OpenGL ES1.0中渲染球体而不是将纹理附加到它来拍摄照片。之后我可以使用传感器值来旋转球体。
但是,我无法弄清楚如何将图片更改为视频。我尝试使用texSubImage2D()逐帧渲染,但它是超级慢。我的视频可能是 4k密度,因为我需要一个好的质量,即使它只显示了一小部分。
我已经阅读了一些关于如何做到这一点的理论知识(即帧缓冲,外部纹理,同步等)但我找不到任何示例对于这些事情,所以一些代码将非常感激 ......
以下是我如何渲染球体,绘制它并为其附加纹理(即我的Sphere类)......
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这是我的渲染器......
import rapid.decoder.BitmapDecoder;
public class Sphere {
/** Buffer holding the vertices. */
private final List<FloatBuffer> mVertexBuffer = new ArrayList<FloatBuffer>();
/** The vertices for the sphere. */
private final List<float[]> mVertices = new ArrayList<float[]>();
/** Buffer holding the texture coordinates. */
private final List<FloatBuffer> mTextureBuffer = new ArrayList<FloatBuffer>();
/** Mapping texture coordinates for the vertices. */
private final List<float[]> mTexture = new ArrayList<float[]>();
/** The texture pointer. */
private final int[] mTextures = new int[1];
/** Total number of strips for the given depth. */
private final int mTotalNumStrips;
public Sphere(final int depth, final float radius) {
// Calculate basic values for the sphere.
this.mTotalNumStrips = Maths.power(2, depth - 1) * 5; //last 5 is related to properties of a icosahedron
final int numVerticesPerStrip = Maths.power(2, depth) * 3;
final double altitudeStepAngle = Maths.rad120 / Maths.power(2, depth);
final double azimuthStepAngle = Maths.rad360 / this.mTotalNumStrips;
double x, y, z, h, altitude, azimuth;
Log.e("mTotalNumStrips", ""+mTotalNumStrips);
Log.e("numVerticesPerStrip", ""+numVerticesPerStrip);
for (int stripNum = 0; stripNum < this.mTotalNumStrips; stripNum++) {
// Setup arrays to hold the points for this strip.
final float[] vertices = new float[numVerticesPerStrip * 3]; // x,y,z
final float[] texturePoints = new float[numVerticesPerStrip * 2]; // 2d texture
int vertexPos = 0;
int texturePos = 0;
// Calculate position of the first vertex in this strip.
altitude = Maths.rad90;
azimuth = stripNum * azimuthStepAngle;
// Draw the rest of this strip.
for (int vertexNum = 0; vertexNum < numVerticesPerStrip; vertexNum += 2) {
// First point - Vertex.
y = radius * Math.sin(altitude);
h = radius * Math.cos(altitude);
z = h * Math.sin(azimuth);
x = h * Math.cos(azimuth);
vertices[vertexPos++] = (float) x;
vertices[vertexPos++] = (float) y;
vertices[vertexPos++] = (float) z;
// First point - Texture.
texturePoints[texturePos++] = (float) (1 + azimuth / Maths.rad360);
texturePoints[texturePos++] = (float) (1 - (altitude + Maths.rad90) / Maths.rad180);
// Second point - Vertex.
altitude -= altitudeStepAngle;
azimuth -= azimuthStepAngle / 2.0;
y = radius * Math.sin(altitude);
h = radius * Math.cos(altitude);
z = h * Math.sin(azimuth);
x = h * Math.cos(azimuth);
vertices[vertexPos++] = (float) x;
vertices[vertexPos++] = (float) y;
vertices[vertexPos++] = (float) z;
// Second point - Texture.
texturePoints[texturePos++] = (float) (1 + azimuth / Maths.rad360);
texturePoints[texturePos++] = (float) (1 - (altitude + Maths.rad90) / Maths.rad180);
azimuth += azimuthStepAngle;
}
this.mVertices.add(vertices);
this.mTexture.add(texturePoints);
ByteBuffer byteBuffer = ByteBuffer.allocateDirect(numVerticesPerStrip * 3 * Float.SIZE);
byteBuffer.order(ByteOrder.nativeOrder());
FloatBuffer fb = byteBuffer.asFloatBuffer();
fb.put(this.mVertices.get(stripNum));
fb.position(0);
this.mVertexBuffer.add(fb);
// Setup texture.
byteBuffer = ByteBuffer.allocateDirect(numVerticesPerStrip * 2 * Float.SIZE);
byteBuffer.order(ByteOrder.nativeOrder());
fb = byteBuffer.asFloatBuffer();
fb.put(this.mTexture.get(stripNum));
fb.position(0);
this.mTextureBuffer.add(fb);
}
}
public void loadGLTexture(final GL10 gl, final Context context, final int texture) {
Bitmap bitmap = BitmapDecoder.from(context.getResources(), texture)
.scale(4048, 2024)
.decode();
// Generate one texture pointer, and bind it to the texture array.
gl.glGenTextures(1, this.mTextures, 0);
gl.glBindTexture(GL10.GL_TEXTURE_2D, this.mTextures[0]);
// Create nearest filtered texture.
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_NEAREST);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER, GL10.GL_LINEAR);
// Use Android GLUtils to specify a two-dimensional texture image from our bitmap.
GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0);
// Tide up.
bitmap.recycle();
}
/**
* The draw method for the square with the GL context.
*
* @param gl Graphics handle.
*/
public void draw(final GL10 gl) {
// bind the previously generated texture.
gl.glBindTexture(GL10.GL_TEXTURE_2D, this.mTextures[0]);
// Point to our buffers.
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
// Set the face rotation, clockwise in this case.
gl.glFrontFace(GL10.GL_CW);
// Point to our vertex buffer.
for (int i = 0; i < this.mTotalNumStrips; i++) {
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, this.mVertexBuffer.get(i));
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, this.mTextureBuffer.get(i));
// Draw the vertices as triangle strip.
gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, this.mVertices.get(i).length / 3);
}
// Disable the client state before leaving.
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
}
答案 0 :(得分:0)
我有一些这类视频纹理问题。我第一次使用ffmpeg进行视频解码,但性能却很差(就像你一样 - 逐帧提取)。为了提高性能,我使用了android默认的mediaplayer。你可以使用表面纹理来创建一个opengl表面(球体,圆柱体,立方体等......),然后在媒体播放器中设置表面
Surface surface = new Surface(mSurface);//mSurface is your surface texture
mMediaPlayer.setSurface(surface);
mMediaPlayer.setScreenOnWhilePlaying(true);
这只是一种技巧。我为一些商业封闭项目做了这个,所以我不能分享代码。我希望我很快就能在github上发布免费代码。