In Lightroom CC, can I export using the same quality as the original jpeg

In Lightroom CC, I work with * .jpg files imported from a mobile phone (Samsung Gallaxy S9), not with RAW files.

I made changes in Lightroom and I export my images.

(Q) What quality should I use when exporting to keep the same quality as the original jpeg image?

My desire is not to introduce artifacts or decrease the quality or to significantly enlarge the file.

I would have thought Quality = 100 to get the best quality, but in some quick tests the file size has increased instead of staying roughly the same size as the original. I'm not sure what that means.

I looked for answers and found these links useful:

  • Does JPEG to JPEG export Lightroom reapplication compression? – request if an original image is of quality 80 and has been modified and re-exported, should the second export be "Quality 100" or "Quality 80".

  • Google search for lightroom exporting jpg images what quality should I use? – Interesting article that explains lighroom export & # 39; s quality works in strips or 93 to 100% were identical, 85-92% were identical. Article so interesting, but it did not answer my question.

  • Google search for Does jpeg file store the quality used when compressing it? but nothing useful appeared. If the JPEG standard stored the compression technique and the values ​​used to generate the image, it might be possible to find the original compression used and use the same value when creating the file. jpeg exported.

  • Google search What quality should I use for JPEG? says: In general, the quality 90 to 100% and more high quality, 80-90% are medium quality and 70-80% is of low quality. Is perfectly logical (not!).

In my case, I'm dealing with images taken from a cellphone, so I'm not sure of the original "quality" of the JPEG image.

limits – Why is an exponent of $ 2n $ necessary in the Dirichlet function?

For those who do not know, a question explaining the definition is in the question here. The definition itself is

$$ lim_ {m to infty} lim_ {n to infty} cos ^ {2n} left (m! pi x right) $$
and evaluates to 1 for rational $ x $ and 0 for irrational $ x $. The part that I don't fully understand is why the exhibitor is $ 2n $ as opposed to just $ n $.

This is a very lax question, but my concern comes from the fact $ n to infty $, $ 2n $ is not necessarily even, let alone an integer, which negates the value of making rational values ​​become $ 1 $ instead of $ pm1 $. It seems that you could, on the other hand, write it as

$$ lim_ {m to infty} lim_ {n to infty} left ( cos ^ {2} left (m! pi x right) right) ^ n $$
although I’m not quite sure it’s the same expression.

My other question is that if the first equation is "correct", it seems that it logically follows that

$$ lim_ {n to infty} (- 1) ^ {2n} = 1 $$
as well as. Is it true?

front end – Frontend Submit Post (repeater field) How to register a new field (clone)?

What should I do to save them all when I add other fields?

It works well on the backend but not on the frontend: /

Template files (everything is in the same file)

        'post_title'    => $post_title,
        'post_type'     => $post_type,
        'post_status'   => 'pending'

        $old = get_post_meta($post_id, 'data_rows', true);
        $new = array();
        $ah_upl = $_POST('al_upl');
        $ah_mbd = $_POST('al_mbd');
        $ah_ttl = $_POST('al_ttl');
        $count = count( $ah_upl );
        for ( $i = 0; $i < $count; $i++ ) {
            if ( $ah_upl($i) != '' ) :
                $new($i)('al_upl') = stripslashes( strip_tags( $ah_upl($i) ) );
                $new($i)('al_mbd') = stripslashes( $ah_mbd($i) );
                $new($i)('al_ttl') = stripslashes( $ah_ttl($i) );

        if ( !empty( $new ) && $new != $old )
            update_post_meta( $post_id, 'data_rows', $new );
        elseif ( empty($new) && $old )
            delete_post_meta( $post_id, 'data_rows', $old );


jQuery to add a new repeater


//first repeater to show
//adding new entries with jQuery

My phone connects to the Internet when it is on, even when I lack data

I turn off the data and wifi and I turn off my phone. When I turn it back on and unlock the phone, the data icon flickers to the “ on '' state and a handful of messages pass through Internet instant messaging applications.

I assumed it was “ normal '' & # 39; & # 39; for my phone, but then I ran out of data (and I'm 95% certain that this is not only the limit set by the user, but by my provider), and always happened.

Recently, and I'm just mentioning that it may be related, I have had pop-ups warning me that various Google services will not work if I have not installed Google Play services . But he is.


OnePlus 5, with the latest software updates (I assume Android 9).

unit – How to translate a prefab made up of a hierarchy of 3D objects

I am trying to translate a prefab of a puzzle piece made up of a hierarchy of cubes but that does not work.

I tried to translate the GameObject using its transformation and the Translate function, it has not moved. And I also tried to translate every child from the GameObject transformation and that didn't budge either. Examination of the value of the transform position in the debugger showed that it had changed, however. "ActiveinHierarchy" is also set to false and I wonder if that could be the problem.

Here is the code for the second method:

enum NanoPieceType

public class GameController : MonoBehaviour
    public GameObject INanoPiece, TNanoPiece, LNanoPiece, ONanoPiece;
    private NanoPieceType currentPiece;
    private int speed;

    void Start()
        currentPiece = (NanoPieceType)Random.Range(0, 3);
        speed = 1;
        CreateNanoPiece((NanoPieceType)currentPiece, new Vector3(0f, 10f, 0f), 
   new Quaternion(0f, 0f, 0f, 0f));


   // Update is called once per frame
   void Update()

        switch (currentPiece)
            case NanoPieceType.IPIECE:
            case NanoPieceType.LPIECE:
            case NanoPieceType.OPIECE:
            case NanoPieceType.TPIECE:



   void MovePieceDown(GameObject obj)
        GameObject child = obj;

        child.transform.Translate(0f, -1.0f*Time.deltaTime, 0f);

        for (int i = 0; i < child.transform.childCount;i++)
            GameObject newObj = child.transform.GetChild(i).gameObject;
            newObj.transform.Translate(0f, -1.0f * Time.deltaTime, 0f);


void CreateNanoPiece(NanoPieceType type, Vector3 pos, Quaternion rot)
    switch (type)
        case NanoPieceType.IPIECE:
            Instantiate(INanoPiece, pos, rot);
        case NanoPieceType.LPIECE:
            Instantiate(LNanoPiece, pos, rot);
        case NanoPieceType.OPIECE:
            Instantiate(ONanoPiece, pos, rot);
        case NanoPieceType.TPIECE:
            Instantiate(TNanoPiece, pos, rot);


dns – Redirect all subdomains of one root to the equivalent subdomain of another root?

I have and

I want to redirect (without being aliased), the same for and, etc., for all subdomains.

I know that I can redirect all subdomains of to a particular subdomain of (for example, and both go to using a generic DNS record, but I'm not sure how to keep the requested subdomain name and apply it with redirection.

Is it only possible?

usa – How to prove the mother-child relationship for the baby passport if the mother's name on the birth certificate is different from the current legal name?

My wife's current legal name is SARAH SMITH. On my child's birth certificate, the line to note the mother says Mother's Name Prior to First Marriage who shows his name as DONGMEI HUANG.

My wife changed her name legally to SARAH SMITH during her citizenship naturalization process.

When we ask for our child's passport, how do we prove the mother-child relationship?

Group a data group by most recent date

Here is the query I have:

FROM biochemical_indicators
INNER JOIN patients 
ON biochemical_indicators.id_patient = patients.id_patient
WHERE patients.status = 1
    biochemical_indicators.rgrtn_biochemical DESC,
    biochemical_indicators.id_indctrs DESC

Here is my result:
enter description of image here

What is marked with the red arrow is what I need as a result, I tried the MAX () function but it did not work.

Someone who can help me solve this problem.

forms – MachineName field: Javascript functions?

In my custom form, I am trying to create web form entities. They need unique machine names. Using the MachineName field in D8, the documentation suggests that we can get the field to be filled in automatically based on entering text from another field, AND there may be a JS callback to call a function that can check if the machine name is unique.

Neither works for me. These are the form elements that I use.

//----------------- general settings ------------------
$form('settings') = array(
  'label' => ('#type' => 'textfield','#title' => 'Form Title'),
  'id'=> array(
    '#type' => 'machine_name',
    'label' => 'hh',
    '#source' => ('label'),
    '#maxlength' => 64,
    '#description' => $this->t('A unique name for this item. It must only contain lowercase letters, numbers, and underscores.'),
    '#machine_name' => array(
      'exists' => array(

Can anyone advise? I have a named callback, but I don't know what it should look like.

functional analysis – C * Morita-invertible algebras

I know the Morita theory of rings and the Hermitian theory Morita of rings with involution, and I am trying to understand some parallels and differences with Morita theory of C * algebras.

In the algebraic version, we are interested in the monoid structure of the Morita equivalence classes of $ R $-algebras (where R is a commutative ring), given by the tensor product on $ R $. In particular, the invertible elements of this monoid are given by the Azumaya algebras on $ R $, and they form the Brauer group of $ R $. Do similar phenomena occur for C * algebras?

For von Neumann algebras, I asked a question about Math.SE, and someone commented that the theory is essentially empty: since type I factors are Morita-trivial, and a tensor product of a factor of type II or III with another factor is again type II or III, in the end, the only way to be morita-invertible is to be morita-trivial.

Do C * algebras offer more theory? I understand that in this context, you have to be a little more careful: the Morita equivalence that I care about is the strong Morita equivalence (as defined by the bimodules of printability). Also, talking about tensor products can be annoying, so maybe I should limit myself to nuclear C * algebras (but if there are Morita-invertibility results for well-chosen tensor products on non-nuclear algebras , I'm also interested in hearing about it).

Obviously, we must limit ourselves to unitary and central algebras, so at the end my question is as follows:

Yes $ A $ is a unitary central C * algebra (possibly nuclear), and there exists $ B $ such as $ A otimes B $ is strongly equivalent to Morita $ mathbb {C} $ (for certain tensing products if $ A $ is not nuclear), does it follow that $ A $ itself is strongly equivalent to Morita $ mathbb {C} $?

I am also interested in similar results for real C * algebras (maybe even more).