TemplateFinder.cpp

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// ANSI C headers
#include <algorithm>
#include <cmath>
#include <cstdlib>
#include <utility>
 
// Qt headers
#include <QFile>
#include <QFileInfo>
#include <QTextStream>
 
// MythTV headers
#include "libmythbase/mythconfig.h"
#include "libmythbase/exitcodes.h"
#include "libmythbase/mythcorecontext.h"
#include "libmythbase/mythdate.h"
#include "libmythbase/mythlogging.h"
#include "libmythbase/mythsystemlegacy.h"
#include "libmythtv/mythframe.h"          /* VideoFrame */
#include "libmythtv/mythplayer.h"
 
// Commercial Flagging headers
#include "BorderDetector.h"
#include "CommDetector2.h"
#include "EdgeDetector.h"
#include "PGMConverter.h"
#include "TemplateFinder.h"
#include "pgm.h"
 
extern "C" {
    #include "libavutil/imgutils.h"
    }
 
using namespace commDetector2;
 
namespace {
 
//returns true on success, false otherwise
bool writeJPG(const QString& prefix, const AVFrame *img, int imgheight)
{
    const int imgwidth = img->linesize[0];
    QFileInfo jpgfi(prefix + ".jpg");
    if (!jpgfi.exists())
    {
        QFile pgmfile(prefix + ".pgm");
        if (!pgmfile.exists())
        {
            QByteArray pfname = pgmfile.fileName().toLocal8Bit();
            if (pgm_write(img->data[0], imgwidth, imgheight,
                          pfname.constData()))
            {
                return false;
            }
        }
 
        QString cmd = QString("convert -quality 50 -resize 192x144 %1 %2")
                      .arg(pgmfile.fileName(), jpgfi.filePath());
        if (myth_system(cmd) != GENERIC_EXIT_OK)
            return false;
 
        if (!pgmfile.remove())
        {
            LOG(VB_COMMFLAG, LOG_ERR, 
                QString("TemplateFinder.writeJPG error removing %1 (%2)")
                    .arg(pgmfile.fileName(), strerror(errno)));
            return false;
        }
    }
    return true;
}
 
int
pgm_scorepixels(unsigned int *scores, int width, int row, int col,
        const AVFrame *src, int srcheight)
{
    /* Every time a pixel is an edge, give it a point. */
    const int   srcwidth = src->linesize[0];
 
    for (int rr = 0; rr < srcheight; rr++)
    {
        for (int cc = 0; cc < srcwidth; cc++)
        {
            if (src->data[0][(rr * srcwidth) + cc])
                scores[((row + rr) * width) + col + cc]++;
        }
    }
 
    return 0;
}
 
int
sort_ascending(const void *aa, const void *bb)
{
    return *(unsigned int*)aa - *(unsigned int*)bb;
}
 
float
bounding_score(const AVFrame *img, int row, int col, int width, int height)
{
    /* Return a value between [0..1] */
    const int       imgwidth = img->linesize[0];
 
    uint score = 0;
    int rr2 = row + height;
    int cc2 = col + width;
    for (int rr = row; rr < rr2; rr++)
    {
        for (int cc = col; cc < cc2; cc++)
        {
            if (img->data[0][(rr * imgwidth) + cc])
                score++;
        }
    }
    return (float)score / (width * height);
}
 
bool
rowisempty(const AVFrame *img, int row, int col, int width)
{
    const int   imgwidth = img->linesize[0];
    for (int cc = col; cc < col + width; cc++)
        if (img->data[0][(row * imgwidth) + cc])
            return false;
    return true;
}
 
bool
colisempty(const AVFrame *img, int col, int row, int height)
{
    const int   imgwidth = img->linesize[0];
    for (int rr = row; rr < row + height; rr++)
        if (img->data[0][(rr * imgwidth) + col])
            return false;
    return true;
}
 
int
bounding_box(const AVFrame *img, int imgheight,
        int minrow, int mincol, int maxrow1, int maxcol1,
        int *prow, int *pcol, int *pwidth, int *pheight)
{
    const int           imgwidth = img->linesize[0];
    /*
     * TUNABLE:
     *
     * Maximum logo size, expressed as a percentage of the content area
     * (adjusting for letterboxing and pillarboxing).
     */
    static constexpr int kMaxWidthPct = 20;
    static constexpr int kMaxHeightPct = 20;
 
    /*
     * TUNABLE:
     *
     * Safety margin to avoid cutting too much of the logo.
     * Higher values cut more, but avoid noise as part of the template..
     * Lower values cut less, but can include noise as part of the template.
     */
    const int           VERTSLOP = std::max(4, imgheight * 1 / 15);
    const int           HORIZSLOP = std::max(4, imgwidth * 1 / 20);
 
    int maxwidth = (maxcol1 - mincol) * kMaxWidthPct / 100;
    int maxheight = (maxrow1 - minrow) * kMaxHeightPct / 100;
 
    int row = minrow;
    int col = mincol;
    int width = maxcol1 - mincol;
    int height = maxrow1 - minrow;
    int newrow = 0;
    int newcol = 0;
    int newright = 0;
    int newbottom = 0;
 
    for (;;)
    {
        bool            improved = false;
 
        LOG(VB_COMMFLAG, LOG_INFO, QString("bounding_box %1x%2@(%3,%4)")
                .arg(width).arg(height).arg(col).arg(row));
 
        /* Chop top. */
        float score = bounding_score(img, row, col, width, height);
        newrow = row;
        for (int ii = 1; ii < height; ii++)
        {
            float newscore =
                bounding_score(img, row + ii, col, width, height - ii);
            if (newscore < score)
                break;
            score = newscore;
            newrow = row + ii;
            improved = true;
        }
 
        /* Chop left. */
        score = bounding_score(img, row, col, width, height);
        newcol = col;
        for (int ii = 1; ii < width; ii++)
        {
            float newscore =
                bounding_score(img, row, col + ii, width - ii, height);
            if (newscore < score)
                break;
            score = newscore;
            newcol = col + ii;
            improved = true;
        }
 
        /* Chop bottom. */
        score = bounding_score(img, row, col, width, height);
        newbottom = row + height;
        for (int ii = 1; ii < height; ii++)
        {
            float newscore =
                bounding_score(img, row, col, width, height - ii);
            if (newscore  < score)
                break;
            score = newscore;
            newbottom = row + height - ii;
            improved = true;
        }
 
        /* Chop right. */
        score = bounding_score(img, row, col, width, height);
        newright = col + width;
        for (int ii = 1; ii < width; ii++)
        {
            float newscore =
                bounding_score(img, row, col, width - ii, height);
            if (newscore < score)
                break;
            score = newscore;
            newright = col + width - ii;
            improved = true;
        }
 
        if (!improved)
            break;
 
        row = newrow;
        col = newcol;
        width = newright - newcol;
        height = newbottom - newrow;
 
        /*
         * Noise edge pixels in the frequency template can sometimes stretch
         * the template area to be larger than it should be.
         *
         * However, noise needs to be distinguished from a uniform distribution
         * of noise pixels (e.g., no real statically-located template). So if
         * the template area is too "large", then some quadrant must have a
         * clear majority of the edge pixels; otherwise we declare failure (no
         * template found).
         *
         * Intuitively, we should simply repeat until a single bounding box is
         * converged upon. However, this requires a more sophisticated
         * bounding_score function that I don't feel like figuring out.
         * Indefinitely repeating with the present bounding_score function will
         * tend to chop off too much. Instead, simply do some sanity checks on
         * the candidate template's size, and prune the template area and
         * repeat if it is too "large".
         */
 
        if (width > maxwidth)
        {
            /* Too wide; test left and right portions. */
            int             chop = width / 3;
            int             chopwidth = width - chop;
 
            float left = bounding_score(img, row, col, chopwidth, height);
            float right = bounding_score(img, row, col + chop, chopwidth, height);
            LOG(VB_COMMFLAG, LOG_INFO, 
                QString("bounding_box too wide (%1 > %2); left=%3, right=%4")
                    .arg(width).arg(maxwidth)
                    .arg(left, 0, 'f', 3).arg(right, 0, 'f', 3));
            float minscore = std::min(left, right);
            float maxscore = std::max(left, right);
            if (maxscore < 3 * minscore / 2)
            {
                /*
                 * Edge pixel distribution too uniform; give up.
                 *
                 * XXX: also fails for horizontally-centered templates ...
                 */
                LOG(VB_COMMFLAG, LOG_ERR, "bounding_box giving up (edge "
                                          "pixels distributed too uniformly)");
                return -1;
            }
 
            if (left < right)
                col += chop;
            width -= chop;
            continue;
        }
 
        if (height > maxheight)
        {
            /* Too tall; test upper and lower portions. */
            int             chop = height / 3;
            int             chopheight = height - chop;
 
            float upper = bounding_score(img, row, col, width, chopheight);
            float lower = bounding_score(img, row + chop, col, width, chopheight);
            LOG(VB_COMMFLAG, LOG_INFO,
                QString("bounding_box too tall (%1 > %2); upper=%3, lower=%4")
                    .arg(height).arg(maxheight)
                    .arg(upper, 0, 'f', 3).arg(lower, 0, 'f', 3));
            float minscore = std::min(upper, lower);
            float maxscore = std::max(upper, lower);
            if (maxscore < 3 * minscore / 2)
            {
                /*
                 * Edge pixel distribution too uniform; give up.
                 *
                 * XXX: also fails for vertically-centered templates ...
                 */
                LOG(VB_COMMFLAG, LOG_ERR, "bounding_box giving up (edge "
                                          "pixel distribution too uniform)");
                return -1;
            }
 
            if (upper < lower)
                row += chop;
            height -= chop;
            continue;
        }
 
        break;
    }
 
    /*
     * The above "chop" algorithm often cuts off the outside edges of the
     * logos because the outside edges don't contribute enough to the score. So
     * compensate by now expanding the bounding box (up to a *SLOP pixels in
     * each direction) to include all edge pixels.
     */
 
    LOG(VB_COMMFLAG, LOG_INFO,
        QString("bounding_box %1x%2@(%3,%4); horizslop=%5,vertslop=%6")
            .arg(width).arg(height).arg(col).arg(row)
            .arg(HORIZSLOP).arg(VERTSLOP));
 
    /* Expand upwards. */
    newrow = row - 1;
    for (;;)
    {
        if (newrow <= minrow)
        {
            newrow = minrow;
            break;
        }
        if (row - newrow >= VERTSLOP)
        {
            newrow = row - VERTSLOP;
            break;
        }
        if (rowisempty(img, newrow, col, width))
        {
            newrow++;
            break;
        }
        newrow--;
    }
    newrow = std::max(minrow, newrow - 1);   /* Empty row on top. */
 
    /* Expand leftwards. */
    newcol = col - 1;
    for (;;)
    {
        if (newcol <= mincol)
        {
            newcol = mincol;
            break;
        }
        if (col - newcol >= HORIZSLOP)
        {
            newcol = col - HORIZSLOP;
            break;
        }
        if (colisempty(img, newcol, row, height))
        {
            newcol++;
            break;
        }
        newcol--;
    }
    newcol = std::max(mincol, newcol - 1);   /* Empty column to left. */
 
    /* Expand rightwards. */
    newright = col + width;
    for (;;)
    {
        if (newright >= maxcol1)
        {
            newright = maxcol1;
            break;
        }
        if (newright - (col + width) >= HORIZSLOP)
        {
            newright = col + width + HORIZSLOP;
            break;
        }
        if (colisempty(img, newright, row, height))
            break;
        newright++;
    }
    newright = std::min(maxcol1, newright + 1);  /* Empty column to right. */
 
    /* Expand downwards. */
    newbottom = row + height;
    for (;;)
    {
        if (newbottom >= maxrow1)
        {
            newbottom = maxrow1;
            break;
        }
        if (newbottom - (row + height) >= VERTSLOP)
        {
            newbottom = row + height + VERTSLOP;
            break;
        }
        if (rowisempty(img, newbottom, col, width))
            break;
        newbottom++;
    }
    newbottom = std::min(maxrow1, newbottom + 1);    /* Empty row on bottom. */
 
    row = newrow;
    col = newcol;
    width = newright - newcol;
    height = newbottom - newrow;
 
    LOG(VB_COMMFLAG, LOG_INFO, QString("bounding_box %1x%2@(%3,%4)")
            .arg(width).arg(height).arg(col).arg(row));
 
    *prow = row;
    *pcol = col;
    *pwidth = width;
    *pheight = height;
    return 0;
}
 
bool
template_alloc(const unsigned int *scores, int width, int height,
        int minrow, int mincol, int maxrow1, int maxcol1, AVFrame *tmpl,
        int *ptmplrow, int *ptmplcol, int *ptmplwidth, int *ptmplheight,
        bool debug_edgecounts, const QString& debugdir)
{
    /*
     * TUNABLE:
     *
     * Higher values select for "stronger" pixels to be in the template, but
     * weak pixels might be missed.
     *
     * Lower values allow more pixels to be included as part of the template,
     * but strong non-template pixels might be included.
     */
    static constexpr float kMinScorePctile = 0.998;
 
    const int    nn = width * height;
    int          ii = 0;
    int          first = 0;
    int          last = 0;
    unsigned int threshscore = 0;
    AVFrame      thresh;
 
    if (av_image_alloc(thresh.data, thresh.linesize,
        width, height, AV_PIX_FMT_GRAY8, IMAGE_ALIGN) < 0)
    {
        LOG(VB_COMMFLAG, LOG_ERR,
            QString("template_alloc av_image_alloc thresh (%1x%2) failed")
                .arg(width).arg(height));
        return false;
    }
 
    std::vector<uint> sortedscores;
    sortedscores.resize(nn);
    memcpy(sortedscores.data(), scores, nn * sizeof(uint));
    qsort(sortedscores.data(), nn, sizeof(uint), sort_ascending);
 
    // Automatically clean up allocation at function exit
    auto cleanup_fn = [&](int* /*x*/) {
        av_freep(reinterpret_cast<void*>(&thresh.data[0]));
    };
    std::unique_ptr<int, decltype(cleanup_fn)> cleanup { &first, cleanup_fn };
 
    if (sortedscores[0] == sortedscores[nn - 1])
    {
        /* All pixels in the template area look the same; no template. */
        LOG(VB_COMMFLAG, LOG_ERR,
            QString("template_alloc: %1x%2 pixels all identical!")
                .arg(width).arg(height));
        return false;
    }
 
    /* Threshold the edge frequences. */
 
    ii = (int)roundf(nn * kMinScorePctile);
    threshscore = sortedscores[ii];
    for (first = ii; first > 0 && sortedscores[first] == threshscore; first--)
        ;
    if (sortedscores[first] != threshscore)
        first++;
    for (last = ii; last < nn - 1 && sortedscores[last] == threshscore; last++)
        ;
    if (sortedscores[last] != threshscore)
        last--;
 
    LOG(VB_COMMFLAG, LOG_INFO, QString("template_alloc wanted %1, got %2-%3")
            .arg(kMinScorePctile, 0, 'f', 6)
            .arg((float)first / nn, 0, 'f', 6)
            .arg((float)last / nn, 0, 'f', 6));
 
    for (ii = 0; ii < nn; ii++)
        thresh.data[0][ii] = scores[ii] >= threshscore ? UCHAR_MAX : 0;
 
    if (debug_edgecounts)
    {
        /* Scores, rescaled to [0..UCHAR_MAX]. */
        AVFrame scored;
        if (av_image_alloc(scored.data, scored.linesize,
            width, height, AV_PIX_FMT_GRAY8, IMAGE_ALIGN) < 0)
        {
            LOG(VB_COMMFLAG, LOG_ERR,
                QString("template_alloc av_image_alloc scored (%1x%2) failed")
                    .arg(width).arg(height));
            return false;
        }
        unsigned int maxscore = sortedscores[nn - 1];
        for (ii = 0; ii < nn; ii++)
            scored.data[0][ii] = scores[ii] * UCHAR_MAX / maxscore;
        bool success = writeJPG(debugdir + "/TemplateFinder-scores", &scored,
                height);
        av_freep(reinterpret_cast<void*>(&scored.data[0]));
        if (!success)
            return false;
 
        /* Thresholded scores. */
        if (!writeJPG(debugdir + "/TemplateFinder-edgecounts", &thresh, height))
            return false;
    }
 
    /* Crop to a minimal bounding box. */
 
    if (bounding_box(&thresh, height, minrow, mincol, maxrow1, maxcol1,
                ptmplrow, ptmplcol, ptmplwidth, ptmplheight))
        return false;
 
    if ((uint)(*ptmplwidth * *ptmplheight) > USHRT_MAX)
    {
        /* Max value of data type of TemplateMatcher::edgematch */
        LOG(VB_COMMFLAG, LOG_ERR,
            QString("template_alloc bounding_box too big (%1x%2)")
                .arg(*ptmplwidth).arg(*ptmplheight));
        return false;
    }
 
    if (av_image_alloc(tmpl->data, tmpl->linesize,
        *ptmplwidth, *ptmplheight, AV_PIX_FMT_GRAY8, IMAGE_ALIGN) < 0)
    {
        LOG(VB_COMMFLAG, LOG_ERR,
            QString("template_alloc av_image_alloc tmpl (%1x%2) failed")
                .arg(*ptmplwidth).arg(*ptmplheight));
        return false;
    }
 
    if (pgm_crop(tmpl, &thresh, height, *ptmplrow, *ptmplcol,
                *ptmplwidth, *ptmplheight))
        return false;
 
    return true;
}
 
bool
analyzeFrameDebug(long long frameno, const AVFrame *pgm, int pgmheight,
        const AVFrame *cropped, const AVFrame *edges, int cropheight,
        int croprow, int cropcol, bool debug_frames, const QString& debugdir)
{
    static constexpr int kDelta = 24;
    static int s_lastrow;
    static int s_lastcol;
    static int s_lastwidth;
    static int s_lastheight;
    const int  cropwidth = cropped->linesize[0];
 
    int rowsame    = abs(s_lastrow - croprow) <= kDelta ? 1 : 0;
    int colsame    = abs(s_lastcol - cropcol) <= kDelta ? 1 : 0;
    int widthsame  = abs(s_lastwidth - cropwidth) <= kDelta ? 1 : 0;
    int heightsame = abs(s_lastheight - cropheight) <= kDelta ? 1 : 0;
 
    if (frameno > 0 && rowsame + colsame + widthsame + heightsame >= 3)
        return true;
 
    LOG(VB_COMMFLAG, LOG_INFO,
        QString("TemplateFinder Frame %1: %2x%3@(%4,%5)")
            .arg(frameno, 5)
            .arg(cropwidth).arg(cropheight)
            .arg(cropcol).arg(croprow));
 
    s_lastrow    = croprow;
    s_lastcol    = cropcol;
    s_lastwidth  = cropwidth;
    s_lastheight = cropheight;
 
    if (debug_frames)
    {
        QString base = QString("%1/TemplateFinder-%2")
            .arg(debugdir).arg(frameno, 5, 10, QChar('0'));
 
        /* PGM greyscale image of frame. */
        if (!writeJPG(base, pgm, pgmheight))
            return false;
 
        /* Cropped template area of frame. */
        if (!writeJPG(base + "-cropped", cropped, cropheight))
            return false;
 
        /* Edges of cropped template area of frame. */
        if (!writeJPG(base + "-edges", edges, cropheight))
            return false;
    }
 
    return true;
}
 
/* NOLINTNEXTLINE(readability-non-const-parameter) */
bool readTemplate(const QString& datafile, int *prow, int *pcol, int *pwidth, int *pheight,
        const QString& tmplfile, AVFrame *tmpl, bool *pvalid)
{
    QFile dfile(datafile);
    QFileInfo dfileinfo(dfile);
 
    if (!dfile.open(QIODevice::ReadOnly))
        return false;
 
    if (!dfileinfo.size())
    {
        /* Dummy file: no template. */
        *pvalid = false;
        return true;
    }
 
    // Read template size information from file.
    QTextStream stream(&dfile);
    stream >> *prow >> *pcol >> *pwidth >> *pheight;
    dfile.close();
 
    if (*pwidth < 0 || *pheight < 0)
    {
        LOG(VB_COMMFLAG, LOG_ERR, QString("readTemplate no saved template"));
        return false;
    }
 
    if (av_image_alloc(tmpl->data, tmpl->linesize,
        *pwidth, *pheight, AV_PIX_FMT_GRAY8, IMAGE_ALIGN) < 0)
    {
        LOG(VB_COMMFLAG, LOG_ERR,
            QString("readTemplate av_image_alloc %1 (%2x%3) failed")
                .arg(tmplfile).arg(*pwidth).arg(*pheight));
        return false;
    }
 
    QByteArray tmfile = tmplfile.toLatin1();
    if (pgm_read(tmpl->data[0], *pwidth, *pheight, tmfile.constData()))
    {
        av_freep(reinterpret_cast<void*>(&tmpl->data[0]));
        return false;
    }
 
    *pvalid = true;
    return true;
}
 
void
writeDummyTemplate(const QString& datafile)
{
    /* Leave a 0-byte file. */
    QFile dfile(datafile);
 
    if (!dfile.open(QIODevice::WriteOnly | QIODevice::Truncate) &&
        dfile.exists())
        (void)dfile.remove();
}
 
bool
writeTemplate(const QString& tmplfile, const AVFrame *tmpl, const QString& datafile,
        int row, int col, int width, int height)
{
    QFile tfile(tmplfile);
 
    QByteArray tmfile = tmplfile.toLatin1();
    if (pgm_write(tmpl->data[0], width, height, tmfile.constData()))
        return false;
 
    QFile dfile(datafile);
    if (!dfile.open(QIODevice::WriteOnly))
        return false;
 
    QTextStream stream(&dfile);
    stream << row << " " << col << "\n" << width << " " << height << "\n";
    dfile.close();
    return true;
}
 
};  /* namespace */
 
TemplateFinder::TemplateFinder(std::shared_ptr<PGMConverter> pgmc,
                               std::shared_ptr<BorderDetector> bd,
                               std::shared_ptr<EdgeDetector> ed,
                               MythPlayer *player, std::chrono::seconds proglen,
                               const QString& debugdir)
  : m_pgmConverter(std::move(pgmc)),
    m_borderDetector(std::move(bd)),
    m_edgeDetector(std::move(ed)),
    m_sampleTime(std::min(proglen / 2, 20 * 60s)),
    m_debugDir(debugdir),
    m_debugData(debugdir + "/TemplateFinder.txt"),
    m_debugTmpl(debugdir + "/TemplateFinder.pgm")
{
    /*
     * TUNABLE:
     *
     * The number of frames desired for sampling to build the template.
     *
     * Higher values should yield a more accurate template, but requires more
     * time.
     */
    unsigned int        samplesNeeded = 300;
 
    /*
     * TUNABLE:
     *
     * The leading amount of time (in seconds) to sample frames for building up
     * the possible template, and the interval between frames for analysis.
     * This affects how soon flagging can start after a recording has begun
     * (a.k.a. "real-time flagging").
     *
     * Sample half of the program length or 20 minutes, whichever is less.
     */
    // m_sampleTime
 
    const float fps = player->GetFrameRate();
 
    m_frameInterval = (int)roundf(m_sampleTime.count() * fps / samplesNeeded);
    m_endFrame = 0 + ((long long)m_frameInterval * samplesNeeded) - 1;
 
    LOG(VB_COMMFLAG, LOG_INFO,
        QString("TemplateFinder: sampleTime=%1s, samplesNeeded=%2, endFrame=%3")
            .arg(m_sampleTime.count()).arg(samplesNeeded).arg(m_endFrame));
 
    /*
     * debugLevel:
     *      0: no extra debugging
     *      1: cache computations into debugdir [O(1) files]
     *      2: extra verbosity [O(nframes)]
     *      3: dump frames into debugdir [O(nframes) files]
     */
    m_debugLevel = gCoreContext->GetNumSetting("TemplateFinderDebugLevel", 0);
 
    if (m_debugLevel >= 1)
    {
        createDebugDirectory(m_debugDir,
            QString("TemplateFinder debugLevel %1").arg(m_debugLevel));
 
        m_debugTemplate = true;
        m_debugEdgeCounts = true;
 
        if (m_debugLevel >= 3)
            m_debugFrames = true;
    }
}
 
TemplateFinder::~TemplateFinder(void)
{
    delete []m_scores;
    av_freep(reinterpret_cast<void*>(&m_tmpl.data[0]));
    av_freep(reinterpret_cast<void*>(&m_cropped.data[0]));
}
 
enum FrameAnalyzer::analyzeFrameResult
TemplateFinder::MythPlayerInited(MythPlayer *player,
                                 [[maybe_unused]] long long nframes)
{
    /*
     * Only detect edges in portions of the frame where we expect to find
     * a template. This serves two purposes:
     *
     *  - Speed: reduce search space.
     *  - Correctness (insofar as the assumption of template location is
     *    correct): don't "pollute" the set of candidate template edges with
     *    the "content" edges in the non-template portions of the frame.
     */
    QString tmpldims;
    QString playerdims;
 
    QSize buf_dim = player->GetVideoBufferSize();
    m_width  = buf_dim.width();
    m_height = buf_dim.height();
    playerdims = QString("%1x%2").arg(m_width).arg(m_height);
 
    if (m_debugTemplate)
    {
        m_tmplDone = readTemplate(m_debugData, &m_tmplRow, &m_tmplCol,
                        &m_tmplWidth, &m_tmplHeight, m_debugTmpl, &m_tmpl,
                        &m_tmplValid);
        if (m_tmplDone)
        {
            tmpldims = m_tmplValid ? QString("%1x%2@(%3,%4)")
                .arg(m_tmplWidth).arg(m_tmplHeight).arg(m_tmplCol).arg(m_tmplRow) :
                    "no template";
 
            LOG(VB_COMMFLAG, LOG_INFO,
                QString("TemplateFinder::MythPlayerInited read %1: %2")
                    .arg(m_debugTmpl, tmpldims));
        }
    }
 
    if (m_pgmConverter->MythPlayerInited(player) ||
        m_borderDetector->MythPlayerInited(player)) {
        av_freep(reinterpret_cast<void*>(&m_tmpl.data[0]));
        return ANALYZE_FATAL;
    }
 
    if (m_tmplDone)
    {
        if (m_tmplValid)
        {
            LOG(VB_COMMFLAG, LOG_INFO,
                QString("TemplateFinder::MythPlayerInited %1 of %2 (%3)")
                    .arg(tmpldims, playerdims, m_debugTmpl));
        }
        return ANALYZE_FINISHED;
    }
 
    LOG(VB_COMMFLAG, LOG_INFO,
        QString("TemplateFinder::MythPlayerInited framesize %1")
            .arg(playerdims));
    m_scores = new unsigned int[m_width * m_height];
 
    return ANALYZE_OK;
}
 
int
TemplateFinder::resetBuffers(int newwidth, int newheight)
{
    if (m_cwidth == newwidth && m_cheight == newheight)
        return 0;
 
    av_freep(reinterpret_cast<void*>(&m_cropped.data[0]));
 
    if (av_image_alloc(m_cropped.data, m_cropped.linesize,
        newwidth, newheight, AV_PIX_FMT_GRAY8, IMAGE_ALIGN) < 0)
    {
        LOG(VB_COMMFLAG, LOG_ERR,
            QString("TemplateFinder::resetBuffers "
                    "av_image_alloc cropped (%1x%2) failed")
                .arg(newwidth).arg(newheight));
        return -1;
    }
 
    m_cwidth = newwidth;
    m_cheight = newheight;
    return 0;
}
 
enum FrameAnalyzer::analyzeFrameResult
TemplateFinder::analyzeFrame(const MythVideoFrame *frame, long long frameno,
        long long *pNextFrame)
{
    /*
     * TUNABLE:
     *
     * When looking for edges in frames, select some percentile of
     * squared-gradient magnitudes (intensities) as candidate edges. (This
     * number conventionally should not go any lower than the 95th percentile;
     * see edge_mark.)
     *
     * Higher values result in fewer edges; faint logos might not be picked up.
     * Lower values result in more edges; non-logo edges might be picked up.
     *
     * The TemplateFinder accumulates all its state in the "scores" array to
     * be processed later by TemplateFinder::finished.
     */
    const int           FRAMESGMPCTILE = 90;
 
    /*
     * TUNABLE:
     *
     * Exclude some portion of the center of the frame from edge analysis.
     * Elminate false edge-detection logo positives from talking-host types of
     * shows where the high-contrast host and clothes (e.g., tie against white
     * shirt against dark jacket) dominates the edges.
     *
     * This has a nice side-effect of reducing the area to be examined (speed
     * optimization).
     */
    static constexpr float kExcludeWidth = 0.5;
    static constexpr float kExcludeHeight = 0.5;
 
    int            pgmwidth= 0;
    int            pgmheight = 0;
    int            croprow= 0;
    int            cropcol = 0;
    int            cropwidth = 0;
    int            cropheight = 0;
 
    if (frameno < m_nextFrame)
    {
        *pNextFrame = m_nextFrame;
        return ANALYZE_OK;
    }
 
    m_nextFrame = frameno + m_frameInterval;
    *pNextFrame = std::min(m_endFrame, m_nextFrame);
 
    try
    {
        const AVFrame *pgm = m_pgmConverter->getImage(frame, frameno, &pgmwidth, &pgmheight);
        if (pgm == nullptr)
            throw 1;
 
        if (!m_borderDetector->getDimensions(pgm, pgmheight, frameno,
                    &croprow, &cropcol, &cropwidth, &cropheight))
        {
            /* Not a blank frame. */
 
            auto start = nowAsDuration<std::chrono::microseconds>();
 
            m_minContentRow = std::min(croprow, m_minContentRow);
            m_minContentCol = std::min(cropcol, m_minContentCol);
            m_maxContentCol1 = std::max(cropcol + cropwidth, m_maxContentCol1);
            m_maxContentRow1 = std::max(croprow + cropheight, m_maxContentRow1);
 
            if (resetBuffers(cropwidth, cropheight))
                throw 2;
 
            if (pgm_crop(&m_cropped, pgm, pgmheight, croprow, cropcol,
                        cropwidth, cropheight))
                throw 3;
 
            /*
             * Translate the excluded area of the screen into "cropped"
             * coordinates.
             */
            int excludewidth  = (int)(pgmwidth * kExcludeWidth);
            int excludeheight = (int)(pgmheight * kExcludeHeight);
            int excluderow = ((pgmheight - excludeheight) / 2) - croprow;
            int excludecol = ((pgmwidth - excludewidth) / 2) - cropcol;
            (void)m_edgeDetector->setExcludeArea(excluderow, excludecol,
                    excludewidth, excludeheight);
 
            const AVFrame *edges =
                m_edgeDetector->detectEdges(&m_cropped, cropheight, FRAMESGMPCTILE);
            if (edges == nullptr)
                throw 4;
 
            if (pgm_scorepixels(m_scores, pgmwidth, croprow, cropcol,
                        edges, cropheight))
                throw 5;
 
            if (m_debugLevel >= 2)
            {
                if (!analyzeFrameDebug(frameno, pgm, pgmheight, &m_cropped, edges,
                            cropheight, croprow, cropcol, m_debugFrames, m_debugDir))
                    throw 6;
            }
 
            auto end = nowAsDuration<std::chrono::microseconds>();
            m_analyzeTime += (end - start);
        }
 
        if (m_nextFrame > m_endFrame)
            return ANALYZE_FINISHED;
 
        return ANALYZE_OK;
    }
    catch (int e)
    {
        LOG(VB_COMMFLAG, LOG_ERR,
            QString("TemplateFinder::analyzeFrame error at frame %1, step %2")
            .arg(frameno).arg(e));
 
        if (m_nextFrame > m_endFrame)
            return ANALYZE_FINISHED;
 
        return ANALYZE_ERROR;
    }
}
 
int
TemplateFinder::finished([[maybe_unused]] long long nframes, bool final)
{
    if (!m_tmplDone)
    {
        if (!template_alloc(m_scores, m_width, m_height,
                    m_minContentRow, m_minContentCol,
                    m_maxContentRow1, m_maxContentCol1,
                    &m_tmpl, &m_tmplRow, &m_tmplCol, &m_tmplWidth, &m_tmplHeight,
                    m_debugEdgeCounts, m_debugDir))
        {
            if (final)
                writeDummyTemplate(m_debugData);
        }
        else
        {
            if (final && m_debugTemplate)
            {
                m_tmplValid = writeTemplate(m_debugTmpl, &m_tmpl, m_debugData,
                                m_tmplRow, m_tmplCol, m_tmplWidth, m_tmplHeight);
                if (!m_tmplValid)
                {
                    av_freep(reinterpret_cast<void*>(&m_tmpl.data[0]));
                    return -1;
                }
 
                LOG(VB_COMMFLAG, LOG_INFO,
                    QString("TemplateFinder::finished wrote %1"
                            " and %2 [%3x%4@(%5,%6)]")
                        .arg(m_debugTmpl, m_debugData)
                        .arg(m_tmplWidth).arg(m_tmplHeight)
                        .arg(m_tmplCol).arg(m_tmplRow));
            }
        }
 
        if (final)
            m_tmplDone = true;
    }
 
    m_borderDetector->setLogoState(this);
 
    return 0;
}
 
int
TemplateFinder::reportTime(void) const
{
    if (m_pgmConverter->reportTime())
        return -1;
 
    if (m_borderDetector->reportTime())
        return -1;
 
    LOG(VB_COMMFLAG, LOG_INFO, QString("TF Time: analyze=%1s")
            .arg(strftimeval(m_analyzeTime)));
    return 0;
}
 
const struct AVFrame *
TemplateFinder::getTemplate(int *prow, int *pcol, int *pwidth, int *pheight)
    const
{
    if (m_tmplValid)
    {
        *prow = m_tmplRow;
        *pcol = m_tmplCol;
        *pwidth = m_tmplWidth;
        *pheight = m_tmplHeight;
        return &m_tmpl;
    }
    return nullptr;
}
 
/* vim: set expandtab tabstop=4 shiftwidth=4: */