Alternative to ffmpeg for iOS

I've been trying to implement ffmpeg in my ios app several weeks. And now I can play several avi files, but other files like a flv, wma, mp4... play slow.

I have spent much time with ffmpeg and opengl and I don't find solution.

I'm looking other alternatives to play this files on ios device.

Someone know other libraries, frameworks, ... that I can use to play this files. No matter if they have business licenses.

Very thanks,

Edited:

Init Shader:

 shader = [[GLShader alloc] initWithFileName:@"render" attributes:[NSDictionary dictionaryWithObjectsAndKeys:
                                                                                             [NSNumber numberWithInt:0], @"position",
                                                                                             [NSNumber numberWithInt:1], @"texCoords", nil]
                                         uniforms:[NSDictionary dictionaryWithObjectsAndKeys:[NSNumber numberWithInt:0], @"sampler0",
                                                                                             [NSNumber numberWithInt:0], @"viewProjectionMatrix",nil]];

render.fsv:

uniform sampler2D sampler0;
varying highp vec2 _texcoord;
void main()
{ gl_FragColor = texture2D(sampler0, _texcoord);}

render.vsf:

attribute vec4 position;
attribute vec2 texCoords;
varying  vec4 colorVarying;
varying vec2 _texcoord;
uniform mat4 viewProjectionMatrix;

void main()
{   _texcoord = texCoords;   
gl_Position = viewProjectionMatrix * position;}

How I can implement your solution in this code?

I've experienced similar problems. There were two bottlenecks:

decoding
conversion from yuv to rgb formats

I solved the second problem by converting image using shaders. It works really fast now (I can render 6 videos simulteneously at 30 fps on iPad2).

Here is part of the fragment shader:

    uniform sampler2D y;
    uniform sampler2D u;
    uniform sampler2D v;

    ...
    y = texture2D(y, vec2(nx,ny)).r;
    u = texture2D(u, vec2(nx, ny)).r - 0.5;
    v = texture2D(v, vec2(nx, ny)).r - 0.5;

    r = y + 1.13983*v;
    g = y - 0.39465*u - 0.58060*v;
    b = y + 2.03211*u;

    gl_FragColor = vec4(r, g, b, 1.0);

NOTE: you have to store y,u,v components in 3 different textures.

nx and ny - are normalized texture coordinates (from 0 to 1 texture ).