sfmt = PIX_FMT_RGB32;
    iwidth = 1280;
    iheight = 360;

    cvideo = avcodec_find_encoder(AV_CODEC_ID_H264);
    svideo = avformat_new_stream(oc, cvideo);

    svideo->codec->pix_fmt       = PIX_FMT_YUV420P;
    svideo->codec->bit_rate      = 921000;
    svideo->codec->width         = iwidth / 2;
    svideo->codec->height        = iheight;
    svideo->codec->time_base.num = 1;
    svideo->codec->time_base.den = FLV_TIMEBASE;
    svideo->codec->codec_tag     = FLV_TAG_TYPE_VIDEO;
    svideo->codec->flags        |= CODEC_FLAG_GLOBAL_HEADER;

    ...

    avpicture_fill(&spicture, buffer, sfmt, w, h);

    SwsContext *swsCtx = sws_getContext(w, h, sfmt,
                                        iwidth,
                                        iheight * 2,
                                        svideo->codec->pix_fmt,
                                        SWS_BICUBIC, NULL, NULL, NULL);

    sws_scale(swsCtx,
              (const uint8_t * const *) spicture.data,
              spicture.linesize,
              0, iheight,
              dpicture.data,
              dpicture.linesize);

    sws_freeContext(swsCtx);