Does anyone know about any (prototype) c# API's for converting video to google's new WebM video format?
+2
A:
A quick google search says: no. But the example encoder looks like it should be easily translatable to C# using P/Invoke. The Encoder Algorithm Interface looks quite manageable. And there's always C++/CLI if everything else fails. Who starts the codeplex project? :-)
Update: As of now, there is a hackish, rudimentary working prototype .NET API. Here you go:
#include "vpx_codec.h"
#define VPX_CODEC_DISABLE_COMPAT 1
#include "vpx_encoder.h"
#include "vp8cx.h"
#define vp8iface (&vpx_codec_vp8_cx_algo)
using namespace System;
namespace WebM
{
namespace VP8
{
namespace Native
{
public ref class VP8Codec
{
private:
vpx_codec_ctx_t* ctx;
VP8Codec(vpx_codec_ctx_t* ctx)
{
this->ctx = ctx;
}
public:
~VP8Codec()
{
vpx_codec_destroy(ctx);
delete ctx;
}
property String^ LastError
{
String^ get()
{
return gcnew String(vpx_codec_error(ctx));
}
}
property String^ LastErrorDetail
{
String^ get()
{
return gcnew String(vpx_codec_error_detail(ctx));
}
}
int Encode()
{
// TODO: do actual encoding
return
vpx_codec_encode(ctx, NULL, 0, 1, 0, VPX_DL_REALTIME);
}
static VP8Codec^ CreateEncoder() // TODO: add 'config' argument
{
vpx_codec_ctx_t* ctx;
vpx_codec_enc_cfg_t cfg;
if(vpx_codec_enc_config_default(vp8iface, &cfg, 0))
{
return nullptr; // TODO: throw exception
}
ctx = new vpx_codec_ctx_t;
if (vpx_codec_enc_init(ctx, vp8iface, &cfg, 0))
{
delete ctx;
return nullptr; // TODO: throw exception
}
return gcnew VP8Codec(ctx);
}
static property int Version
{
int get()
{
return vpx_codec_version();
}
}
static property String^ VersionString
{
String^ get()
{
return gcnew String(vpx_codec_version_str());
}
}
static property String^ BuildConfig
{
String^ get()
{
return gcnew String(vpx_codec_build_config());
}
}
static String^ GetErrorDescription(int errorCode)
{
return gcnew String(
vpx_codec_err_to_string((vpx_codec_err_t)errorCode));
}
static property String^ IfaceName
{
String^ get()
{
return gcnew String(vpx_codec_iface_name(vp8iface));
}
}
};
}
}
}
You should be able to link this against vpxmtd.lib from the libvpx Windows build. I wasn't able to get rid of one warning, but so far it seems to work. My C++/CLI is a bit rusty, though, so there may be some memory leaks in the code.
Test program:
namespace WebM.VP8
{
using System;
using WebM.VP8.Native;
public class Program
{
public static void Main()
{
using (var encoder = VP8Codec.CreateEncoder())
{
Console.WriteLine(encoder.Encode());
}
}
}
}
dtb
2010-05-20 13:43:20
Very helpful. Thanks a lot.
klausbyskov
2010-05-21 09:13:03