if (vst->codec.aspect_ratio == 16.0 / 9.0)
if ((int)(vst->codec.aspect_ratio * 10) == 17)
DVMuxContext* dv_init_mux(AVFormatContext* s){    DVMuxContext *c;    AVStream *vst;    AVStream *ast;    c = av_mallocz(sizeof(DVMuxContext));    if (!c)        return NULL;    if (s->nb_streams != 2)        goto bail_out;    /* We have to sort out where audio and where video stream is */    if (s->streams[0]->codec.codec_type == CODEC_TYPE_VIDEO &&        s->streams[1]->codec.codec_type == CODEC_TYPE_AUDIO) {       vst = s->streams[0];       ast = s->streams[1];    }    else if (s->streams[1]->codec.codec_type == CODEC_TYPE_VIDEO &&             s->streams[0]->codec.codec_type == CODEC_TYPE_AUDIO) {           vst = s->streams[1];           ast = s->streams[0];    } else        goto bail_out;      /* Some checks -- DV format is very picky about its incoming streams */    if (vst->codec.codec_id != CODEC_ID_DVVIDEO ||	ast->codec.codec_id != CODEC_ID_PCM_S16LE)       goto bail_out;    if (ast->codec.sample_rate != 48000 ||	ast->codec.channels != 2)       goto bail_out;    c->sys = dv_codec_profile(&vst->codec);    if (!c->sys)	goto bail_out;        /* Ok, everything seems to be in working order */    c->frames = 0;    c->has_audio = c->has_video = 0;    c->start_time = time(NULL);    c->aspect = 0; /* 4:3 is the default */    if (vst->codec.aspect_ratio == 16.0 / 9.0)        c->aspect = 0x07;    if (fifo_init(&c->audio_data, 100*AVCODEC_MAX_AUDIO_FRAME_SIZE) < 0)        goto bail_out;    dv_format_frame(c, &c->frame_buf[0]);    return c;    bail_out:    av_free(c);    return NULL;}