Rendering to Video need help

SDL Development
1

Having some trouble writing SDL_Surface to to ffmpeg.

Creating a Surface

SDL_CreateRGBSurface(0, width, height, 32, rmask, gmask, bmask, amask);

Saves pixels into the frame

SDL_RenderReadPixels(
          renderer,
          NULL,
          SDL_PIXELFORMAT_RGBA32,
          surface->pixels,
          surface->pitch
 );

Later uses the pixels

uint8_t* pixels = (uint8_t*)surface->pixels;
   
cctx = avcodec_alloc_context3(codec);
stream->codecpar->format = AV_PIX_FMT_YUV420P;

// gets a new frame
videoFrame = av_frame_alloc();

int inLinesize[1] = { 3 * cctx->width }; // not sure

if (!swsCtx) {
    swsCtx = sws_getContext(cctx->width, cctx->height, AV_PIX_FMT_RGB24, cctx->width, cctx->height, AV_PIX_FMT_YUV420P, SWS_BICUBIC, 0, 0, 0);
}

Adds the pixels to scale

sws_scale(swsCtx, &pixels, inLinesize, 0, cctx->height, videoFrame->data, videoFrame->linesize);

The result on the video frame on the right is wrong, video size and some pixels are correct.

problem.PNG
problem.PNG2317×1345 1.3 MB

Any experienced ffmpeg people who has an idea?