[alsa-devel] [PATCH v4 3/5] media: i2c: Add TDA1997x HDMI receiver driver

Hans Verkuil hverkuil at xs4all.nl
Thu Dec 14 15:26:57 CET 2017


On 14/12/17 00:35, Tim Harvey wrote:
>>> Close. What is missing is a check of the AVI InfoFrame: if it has an explicit
>>> colorimetry then use that. E.g. check for HDMI_COLORIMETRY_ITU_601 or ITU_709
>>> and set the colorspace accordingly. Otherwise fall back to what you have here.
>>>
>>
>> This function currently matches adv7604/adv7842 where they don't look
>> at colorimetry (but I do see a TODO in adv748x_hdmi_fill_format to
>> look at this) so I don't have an example and may not understand.
>>
>> Do you mean:
>>
>>        format->colorspace = V4L2_COLORSPACE_SRGB;
>>        if (bt->flags & V4L2_DV_FL_IS_CE_VIDEO) {
>>                 if ((state->colorimetry == HDMI_COLORIMETRY_ITU_601) ||
>>                     (state->colorimetry == HDMI_COLORIMETRY_ITU_709))
>>                         format->colorspace = state->colorspace;
>>                 else
>>                         format->colorspace = is_sd(bt->height) ?
>>                                 V4L2_COLORSPACE_SMPTE170M :
>> V4L2_COLORSPACE_REC709;
>>         }
>>
>> Also during more testing I've found that I'm not capturing interlaced
>> properly and know I at least need:
>>
>> -        format->field = V4L2_FIELD_NONE;
>> +        format->field = (bt->interlaced) ?
>> +                V4L2_FIELD_ALTERNATE : V4L2_FIELD_NONE;
>>
>> I'm still not quite capturing interlaced yet but I think its an issue
>> of setting up the media pipeline improperly.
>>
> 
> Hans,
> 
> Did you see this question above? I'm not quite understanding what you
> want me to do for filling in colorspace and don't see any examples in
> the existing drivers that appear to look at colorimetry for this.

Yeah, I missed that question. I started answering that yesterday, but then
I realized that it would be better if I would make a helper function for
v4l2-dv-timings. The rules are complex so coding that in a single place
that everyone can use is the smart thing to do.

I hope to finish it tomorrow (too many interruptions today).

Regards,

	Hans



More information about the Alsa-devel mailing list