将专用的NV12视频帧转换为RGB [英] Converting specialized NV12 video frames to RGB

问题描述

我有一个使用Android MediaCodec解码的H264流.当我查询输出MediaFormat时，颜色格式为2141391875.显然，这是一种特殊的NV12变体，称为HAL_PIXEL_FORMAT_NV12_ADRENO_TILED.这是在Nexus 7(2013)上实现的.

I have an H264 stream that's decoded using an Android MediaCodec. When I query the output MediaFormat, the color format is 2141391875. Apparently, that's a specialized NV12 variant known as HAL_PIXEL_FORMAT_NV12_ADRENO_TILED. This is on a Nexus 7 (2013).

我想获取此数据并将其转换为RGB，以便创建位图.我发现StackOverflow帖子将其他格式转换为RGB，而不是此格式.我试过其他文章中的代码，结果只是颜色的条纹. (要查看位图，我在与Surface相关联的Canvas上进行绘制，并以JPEG格式将其写出-两种情况下看起来都相同.)

I want to take this data and convert it to RGB so I can create a Bitmap. I've found StackOverflow posts for converting other formats to RGB, not this format. I've tried code from those other posts, the result is just streaks of color. (To view the Bitmap, I draw on the Canvas associated with a Surface, as well as write it out as a JPEG -- it looks the same in both cases.)

如何将特定数据转换为RGB?

How can I convert this particular data to RGB?

推荐答案

2141391875十进制为0x7FA30C03(十六进制)，根据

2141391875 decimal is 0x7FA30C03 in hex, which according to this header file is OMX_QCOM_COLOR_FormatYUV420PackedSemiPlanar64x32Tile2m8ka. Which amounts to the same thing as the constant you found: this is a proprietary Qualcomm color format.

最简单(也是最快)的转换方法是让OpenGL ES为您完成工作.例如，参见 ExtractMpegFramesTest ，它将视频帧解码为SurfaceTexture，将纹理渲染到屏幕外表面，然后使用glReadPixels()读出像素. GLES驱动程序将为您处理RGB转换.

The easiest (and fastest) way to convert it is to let OpenGL ES do the work for you. See for example ExtractMpegFramesTest, which decodes video frames to a SurfaceTexture, renders the texture to an off-screen surface, and then reads the pixels out with glReadPixels(). The GLES driver will handle the RGB conversion for you.

如果您想自己进行转换，则需要对颜色格式进行逆向工程，或者找一个已经这样做并且愿意分享的人.

If you want to do the conversion yourself, you will need to reverse-engineer the color format, or find someone who has done so already and is willing to share.

这篇关于将专用的NV12视频帧转换为RGB的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！