/src/ffmpegthumbs/ffmpegthumbnailer.cpp

Source
/*
    SPDX-FileCopyrightText: 2010 Dirk Vanden Boer <dirk.vdb@gmail.com>
    SPDX-FileCopyrightText: 2020 Heiko Schäfer <heiko@rangun.de>

    SPDX-License-Identifier: GPL-2.0-or-later
*/

#include "ffmpegthumbnailer.h"
#include "ffmpegthumbnailersettings5.h"
#include "ffmpegthumbs_debug.h"

#include <limits>

#include <KPluginFactory>
#include <QImage>

extern "C" {
#include <libavformat/avformat.h>
#include <libavutil/dict.h>
#include <libavutil/log.h>
}

namespace {
struct FFmpegLogHandler {
    static void handleMessage(void *ptr, int level, const char *fmt, va_list vargs) {
        Q_UNUSED(ptr);

        const QString message = QString::vasprintf(fmt, vargs);

        switch(level) {
        case AV_LOG_PANIC: // ffmpeg will crash now
            qCCritical(ffmpegthumbs_LOG) << message;
            break;
        case AV_LOG_FATAL: // fatal as in can't decode, not crash
        case AV_LOG_ERROR:
        case AV_LOG_WARNING:
            qCWarning(ffmpegthumbs_LOG) << message;
            break;
        case AV_LOG_INFO:
            qCInfo(ffmpegthumbs_LOG) << message;
            break;
        case AV_LOG_VERBOSE:
        case AV_LOG_DEBUG:
        case AV_LOG_TRACE:
            qCDebug(ffmpegthumbs_LOG) << message;
            break;
        default:
            qCWarning(ffmpegthumbs_LOG) << "unhandled log level" << level << message;
            break;
        }
    }

    FFmpegLogHandler() {
        av_log_set_callback(&FFmpegLogHandler::handleMessage);
    }
};
} //namespace

FFMpegThumbnailer::FFMpegThumbnailer(QObject *parent, const QVariantList &args)
    : KIO::ThumbnailCreator(parent, args)
{
    FFMpegThumbnailerSettings* settings = FFMpegThumbnailerSettings::self();
    if (settings->filmstrip()) {
        m_Thumbnailer.addFilter(&m_FilmStrip);
    }
    m_thumbCache.setMaxCost(settings->cacheSize());
}

FFMpegThumbnailer::~FFMpegThumbnailer()
{
}

KIO::ThumbnailResult FFMpegThumbnailer::create(const KIO::ThumbnailRequest &request)
{
    int seqIdx = static_cast<int>(request.sequenceIndex());
    if (seqIdx < 0) {
        seqIdx = 0;
    }

    QList<int> seekPercentages = FFMpegThumbnailerSettings::sequenceSeekPercentages();
    if (seekPercentages.isEmpty()) {
        seekPercentages.append(20);
    }

    // We might have an embedded thumb in the video file, so we have to add 1. This gets corrected
    // later if we don't have one.
    seqIdx %= static_cast<int>(seekPercentages.size()) + 1;

    const QString path = request.url().toLocalFile();
    const QString cacheKey = QStringLiteral("%1$%2@%3").arg(path).arg(request.sequenceIndex()).arg(request.targetSize().width());

    QImage* cachedImg = m_thumbCache[cacheKey];
    if (cachedImg) {
        return pass(*cachedImg);
    }

    // Try reading thumbnail embedded into video file
    QByteArray ba = path.toLocal8Bit();
    AVFormatContext* ct = avformat_alloc_context();
    AVPacket* pic = nullptr;

    // No matter the seqIdx, we have to know if the video has an embedded cover, even if we then don't return
    // it. We could cache it to avoid repeating this for higher seqIdx values, but this should be fast enough
    // to not be noticeable and caching adds unnecessary complexity.
    if (ct && !avformat_open_input(&ct,ba.data(), nullptr, nullptr)) {

        // Using an priority system based on size or filename (matroska specification) to select the most suitable picture
        int bestPrio = 0;
        for (size_t i = 0; i < ct->nb_streams; ++i) {
            if (ct->streams[i]->disposition & AV_DISPOSITION_ATTACHED_PIC) {
                int prio = 0;
                AVDictionaryEntry* fname = av_dict_get(ct->streams[i]->metadata, "filename", nullptr ,0);
                if (fname) {
                    QString filename(QString::fromUtf8(fname->value));
                    QString noextname = filename.section(QLatin1Char('.'), 0);
                    // Prefer landscape and larger
                    if (noextname == QStringLiteral("cover_land")) {
                        prio = std::numeric_limits<int>::max();
                    }
                    else if (noextname == QStringLiteral("small_cover_land")) {
                        prio = std::numeric_limits<int>::max()-1;
                    }
                    else if (noextname == QStringLiteral("cover")) {
                        prio = std::numeric_limits<int>::max()-2;
                    }
                    else if (noextname == QStringLiteral("small_cover")) {
                        prio = std::numeric_limits<int>::max()-3;
                    }
                    else {
                        prio = ct->streams[i]->attached_pic.size;
                    }
                }
                else {
                    prio = ct->streams[i]->attached_pic.size;
                }
                if (prio > bestPrio) {
                    pic = &(ct->streams[i]->attached_pic);
                    bestPrio = prio;
                }
            }
        }
    }

    auto res = KIO::ThumbnailResult::fail();
    if (pic) {
        QImage img;
        img.loadFromData(pic->data, pic->size);
        res = pass(img);
    }
    avformat_close_input(&ct);

    float wraparoundPoint = 1.0f;
    if (!res.image().isNull()) {
        // Video file has an embedded thumbnail -> return it for seqIdx=0 and shift the regular
        // seek percentages one to the right

        res.setSequenceIndexWraparoundPoint(updatedSequenceIndexWraparoundPoint(1.0f));

        if (seqIdx == 0) {
            return res;
        }

        seqIdx--;
    } else {
        wraparoundPoint = updatedSequenceIndexWraparoundPoint(0.0f);
    }

    // The previous modulo could be wrong now if the video had an embedded thumbnail.
    seqIdx %= seekPercentages.size();

    m_Thumbnailer.setThumbnailSize(request.targetSize().width());
    m_Thumbnailer.setSeekPercentage(seekPercentages[seqIdx]);
    //Smart frame selection is very slow compared to the fixed detection
    //TODO: Use smart detection if the image is single colored.
    //m_Thumbnailer.setSmartFrameSelection(true);
    QImage img;
    m_Thumbnailer.generateThumbnail(path, img);

    if (!img.isNull()) {
        // seqIdx 0 will be served from KIO's regular thumbnail cache.
        if (static_cast<int>(request.sequenceIndex()) != 0) {
            const int cacheCost = static_cast<int>((img.sizeInBytes() + 1023) / 1024);
            m_thumbCache.insert(cacheKey, new QImage(img), cacheCost);
        }

        return pass(img, wraparoundPoint);
    }

    return KIO::ThumbnailResult::fail();
}

float FFMpegThumbnailer::updatedSequenceIndexWraparoundPoint(float offset)
{
    float wraparoundPoint = offset;
    if (!FFMpegThumbnailerSettings::sequenceSeekPercentages().isEmpty()) {
        wraparoundPoint += FFMpegThumbnailerSettings::sequenceSeekPercentages().size();
    } else {
        wraparoundPoint += 1.0f;
    }

    return wraparoundPoint;
}

K_PLUGIN_CLASS_WITH_JSON(FFMpegThumbnailer, "ffmpegthumbs.json")

#include "ffmpegthumbnailer.moc"
#include "moc_ffmpegthumbnailer.cpp"

Coverage Report

Created: 2026-01-25 07:18

Line	Count	Source
1		/*
2		SPDX-FileCopyrightText: 2010 Dirk Vanden Boer <dirk.vdb@gmail.com>
3		SPDX-FileCopyrightText: 2020 Heiko Schäfer <heiko@rangun.de>
4
5		SPDX-License-Identifier: GPL-2.0-or-later
6		*/
7
8		#include "ffmpegthumbnailer.h"
9		#include "ffmpegthumbnailersettings5.h"
10		#include "ffmpegthumbs_debug.h"
11
12		#include <limits>
13
14		#include <KPluginFactory>
15		#include <QImage>
16
17		extern "C" {
18		#include <libavformat/avformat.h>
19		#include <libavutil/dict.h>
20		#include <libavutil/log.h>
21		}
22
23		namespace {
24		struct FFmpegLogHandler {
25	0	static void handleMessage(void ptr, int level, const char fmt, va_list vargs) {
26	0	Q_UNUSED(ptr);
27	0
28	0	const QString message = QString::vasprintf(fmt, vargs);
29	0
30	0	switch(level) {
31	0	case AV_LOG_PANIC: // ffmpeg will crash now
32	0	qCCritical(ffmpegthumbs_LOG) << message;
33	0	break;
34	0	case AV_LOG_FATAL: // fatal as in can't decode, not crash
35	0	case AV_LOG_ERROR:
36	0	case AV_LOG_WARNING:
37	0	qCWarning(ffmpegthumbs_LOG) << message;
38	0	break;
39	0	case AV_LOG_INFO:
40	0	qCInfo(ffmpegthumbs_LOG) << message;
41	0	break;
42	0	case AV_LOG_VERBOSE:
43	0	case AV_LOG_DEBUG:
44	0	case AV_LOG_TRACE:
45	0	qCDebug(ffmpegthumbs_LOG) << message;
46	0	break;
47	0	default:
48	0	qCWarning(ffmpegthumbs_LOG) << "unhandled log level" << level << message;
49	0	break;
50	0	}
51	0	}
52
53	0	FFmpegLogHandler() {
54	0	av_log_set_callback(&FFmpegLogHandler::handleMessage);
55	0	}
56		};
57		} //namespace
58
59		FFMpegThumbnailer::FFMpegThumbnailer(QObject *parent, const QVariantList &args)
60	682	: KIO::ThumbnailCreator(parent, args)
61	682	{
62	682	FFMpegThumbnailerSettings* settings = FFMpegThumbnailerSettings::self();
63	682	if (settings->filmstrip()) {
64	682	m_Thumbnailer.addFilter(&m_FilmStrip);
65	682	}
66	682	m_thumbCache.setMaxCost(settings->cacheSize());
67	682	}
68
69		FFMpegThumbnailer::~FFMpegThumbnailer()
70	682	{
71	682	}
72
73		KIO::ThumbnailResult FFMpegThumbnailer::create(const KIO::ThumbnailRequest &request)
74	682	{
75	682	int seqIdx = static_cast<int>(request.sequenceIndex());
76	682	if (seqIdx < 0) {
77	0	seqIdx = 0;
78	0	}
79
80	682	QList<int> seekPercentages = FFMpegThumbnailerSettings::sequenceSeekPercentages();
81	682	if (seekPercentages.isEmpty()) {
82	0	seekPercentages.append(20);
83	0	}
84
85		// We might have an embedded thumb in the video file, so we have to add 1. This gets corrected
86		// later if we don't have one.
87	682	seqIdx %= static_cast<int>(seekPercentages.size()) + 1;
88
89	682	const QString path = request.url().toLocalFile();
90	682	const QString cacheKey = QStringLiteral("%1$%2@%3").arg(path).arg(request.sequenceIndex()).arg(request.targetSize().width());
91
92	682	QImage* cachedImg = m_thumbCache[cacheKey];
93	682	if (cachedImg) {
94	0	return pass(*cachedImg);
95	0	}
96
97		// Try reading thumbnail embedded into video file
98	682	QByteArray ba = path.toLocal8Bit();
99	682	AVFormatContext* ct = avformat_alloc_context();
100	682	AVPacket* pic = nullptr;
101
102		// No matter the seqIdx, we have to know if the video has an embedded cover, even if we then don't return
103		// it. We could cache it to avoid repeating this for higher seqIdx values, but this should be fast enough
104		// to not be noticeable and caching adds unnecessary complexity.
105	682	if (ct && !avformat_open_input(&ct,ba.data(), nullptr, nullptr)) {
106
107		// Using an priority system based on size or filename (matroska specification) to select the most suitable picture
108	0	int bestPrio = 0;
109	0	for (size_t i = 0; i < ct->nb_streams; ++i) {
110	0	if (ct->streams[i]->disposition & AV_DISPOSITION_ATTACHED_PIC) {
111	0	int prio = 0;
112	0	AVDictionaryEntry* fname = av_dict_get(ct->streams[i]->metadata, "filename", nullptr ,0);
113	0	if (fname) {
114	0	QString filename(QString::fromUtf8(fname->value));
115	0	QString noextname = filename.section(QLatin1Char('.'), 0);
116		// Prefer landscape and larger
117	0	if (noextname == QStringLiteral("cover_land")) {
118	0	prio = std::numeric_limits<int>::max();
119	0	}
120	0	else if (noextname == QStringLiteral("small_cover_land")) {
121	0	prio = std::numeric_limits<int>::max()-1;
122	0	}
123	0	else if (noextname == QStringLiteral("cover")) {
124	0	prio = std::numeric_limits<int>::max()-2;
125	0	}
126	0	else if (noextname == QStringLiteral("small_cover")) {
127	0	prio = std::numeric_limits<int>::max()-3;
128	0	}
129	0	else {
130	0	prio = ct->streams[i]->attached_pic.size;
131	0	}
132	0	}
133	0	else {
134	0	prio = ct->streams[i]->attached_pic.size;
135	0	}
136	0	if (prio > bestPrio) {
137	0	pic = &(ct->streams[i]->attached_pic);
138	0	bestPrio = prio;
139	0	}
140	0	}
141	0	}
142	0	}
143
144	682	auto res = KIO::ThumbnailResult::fail();
145	682	if (pic) {
146	0	QImage img;
147	0	img.loadFromData(pic->data, pic->size);
148	0	res = pass(img);
149	0	}
150	682	avformat_close_input(&ct);
151
152	682	float wraparoundPoint = 1.0f;
153	682	if (!res.image().isNull()) {
154		// Video file has an embedded thumbnail -> return it for seqIdx=0 and shift the regular
155		// seek percentages one to the right
156
157	0	res.setSequenceIndexWraparoundPoint(updatedSequenceIndexWraparoundPoint(1.0f));
158
159	0	if (seqIdx == 0) {
160	0	return res;
161	0	}
162
163	0	seqIdx--;
164	682	} else {
165	682	wraparoundPoint = updatedSequenceIndexWraparoundPoint(0.0f);
166	682	}
167
168		// The previous modulo could be wrong now if the video had an embedded thumbnail.
169	682	seqIdx %= seekPercentages.size();
170
171	682	m_Thumbnailer.setThumbnailSize(request.targetSize().width());
172	682	m_Thumbnailer.setSeekPercentage(seekPercentages[seqIdx]);
173		//Smart frame selection is very slow compared to the fixed detection
174		//TODO: Use smart detection if the image is single colored.
175		//m_Thumbnailer.setSmartFrameSelection(true);
176	682	QImage img;
177	682	m_Thumbnailer.generateThumbnail(path, img);
178
179	682	if (!img.isNull()) {
180		// seqIdx 0 will be served from KIO's regular thumbnail cache.
181	0	if (static_cast<int>(request.sequenceIndex()) != 0) {
182	0	const int cacheCost = static_cast<int>((img.sizeInBytes() + 1023) / 1024);
183	0	m_thumbCache.insert(cacheKey, new QImage(img), cacheCost);
184	0	}
185
186	0	return pass(img, wraparoundPoint);
187	0	}
188
189	682	return KIO::ThumbnailResult::fail();
190	682	}
191
192		float FFMpegThumbnailer::updatedSequenceIndexWraparoundPoint(float offset)
193	682	{
194	682	float wraparoundPoint = offset;
195	682	if (!FFMpegThumbnailerSettings::sequenceSeekPercentages().isEmpty()) {
196	682	wraparoundPoint += FFMpegThumbnailerSettings::sequenceSeekPercentages().size();
197	682	} else {
198	0	wraparoundPoint += 1.0f;
199	0	}
200
201	682	return wraparoundPoint;
202	682	}
203
204		K_PLUGIN_CLASS_WITH_JSON(FFMpegThumbnailer, "ffmpegthumbs.json") Unexecuted instantiation: ffmpegthumbs_factory::tr(char const, char const, int) Unexecuted instantiation: ffmpegthumbs_factory::~ffmpegthumbs_factory()
205
206		#include "ffmpegthumbnailer.moc"
207		#include "moc_ffmpegthumbnailer.cpp"