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Merged
deepin-bot merged 1 commit into from
Jul 21, 2026
Merged

feat: Add the logic for switching cameras by USB groups. #500

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10 changes: 10 additions & 0 deletions src/assets/org.deepin.camera.encode.json
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Original file line number Diff line number Diff line change
Expand Up @@ -84,6 +84,16 @@
"description": "is preview no delay or not",
"permissions": "readwrite",
"visibility": "private"
},
"enableUsbGroup": {
"value": false,
"serial": 0,
"flags": ["global"],
"name": "enable USB group",
"name[zh_CN]": "是否启用USB摄像头分组",
"description": "Enable USB group",
"permissions": "readwrite",
"visibility": "private"
}
}
}
6 changes: 6 additions & 0 deletions src/main.cpp
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Expand Up @@ -215,6 +215,12 @@ int main(int argc, char *argv[])
DataManager::instance()->setPreviewNoDelay(dconfig->value("previewNoDelay", false).toBool());
}

if (dconfig && dconfig->isValid() && dconfig->keyList().contains("enableUsbGroup")) {
bool enable = dconfig->value("enableUsbGroup").toBool();
qInfo() << "enable USB group:" << enable;
DataManager::instance()->setEnableUsbGroup(enable);
}

if (!libVaDriverName.isEmpty()) {
qputenv("LIBVA_DRIVER_NAME", libVaDriverName.toLocal8Bit());
}
Expand Down
15 changes: 13 additions & 2 deletions src/src/basepub/datamanager.h
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Original file line number Diff line number Diff line change
@@ -1,5 +1,5 @@
// Copyright (C) 2020 ~ 2021 Uniontech Software Technology Co.,Ltd.
// SPDX-FileCopyrightText: 2023 UnionTech Software Technology Co., Ltd.
// Copyright (C) 2020 - 2026 Uniontech Software Technology Co.,Ltd.
// SPDX-FileCopyrightText: 2023 - 2026 UnionTech Software Technology Co., Ltd.
//
// SPDX-License-Identifier: GPL-3.0-or-later

Expand Down Expand Up @@ -165,6 +165,16 @@ class DataManager: public QObject
*/
bool isPreviewNoDelay() const { return m_isPreviewNoDelay; };

/**
* @brief 设置是否启用USB摄像头分组
* @param enable
*/
void setEnableUsbGroup(bool enable) { m_enableUsbGroup = enable; };
/**
* @brief 获取是否启用USB摄像头分组
* @return
*/
bool isEnableUsbGroup() const { return m_enableUsbGroup; };
private:
DataManager();
static DataManager *m_dataManager;
Expand All @@ -176,5 +186,6 @@ class DataManager: public QObject
bool m_H264EncoderExists;
bool m_isSupportCameraSwitch = false; // 是否带有摄像头开关
bool m_isPreviewNoDelay = false; // 是否预览无延迟
bool m_enableUsbGroup = false; // 是否启用USB摄像头分组
};
#endif // DATAMANAGER_H
129 changes: 105 additions & 24 deletions src/src/videowidget.cpp
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Expand Up @@ -1243,39 +1243,89 @@ void videowidget::onChangeDev()
}

v4l2_device_list_t *devlist = get_device_list();
if (devlist->num_devices == 2) {
qDebug() << "device list has 2 devices";
for (int i = 0 ; i < devlist->num_devices; i++) {
QString str1 = QString(devlist->list_devices[i].device);
if (str != str1) {
if (E_OK == switchCamera(devlist->list_devices[i].device, devlist->list_devices[i].name)) {
break;
if (devlist == nullptr) {
qWarning() << "get device list FAILED";
return;
}

// USB摄像头分组相关逻辑来自xiwo分支，是否开启由DConfig控制
int groupNum = 1;
QVector<QPair<QString, QVector<v4l2_dev_sys_data_t *>>> vGroupData;
Comment on lines +1252 to +1253

@sourcery-ai sourcery-ai Bot Jul 21, 2026

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suggestion (bug_risk): Consider clearing vGroupData inside getUSBCameraGroup to avoid accidental reuse bugs.

The function’s correctness currently depends on callers ensuring vGroupData is empty. If a future caller passes a non-empty vector, the function will append to existing data, which can break the grouping logic. Clearing vGroupData at the start of getUSBCameraGroup would make the helper robust and independent of caller assumptions.

Suggested implementation:

int VideoWidget::getUSBCameraGroup(usb_dev_list_t *devlist, QVector<QPair<QString, QVector<v4l2_dev_sys_data_t *>>> &vGroupData)
{
    // 确保每次调用从空的分组数据开始，避免在非空 vGroupData 上追加导致分组逻辑异常
    vGroupData.clear();

If the function signature differs (e.g. not a member of VideoWidget, or parameter types/names vary), adjust the SEARCH line to match the exact function declaration of getUSBCameraGroup and keep the vGroupData.clear(); as the first statement in the function body. No changes are needed at the call site shown in your snippet, since clearing is handled internally by the helper.

// 如果未启用USB摄像头分组，则分组数默认为1，保持原有逻辑；
// 如果启用USB摄像头分组，则实际获取USB分组情况，根据分组结果进行处理；
if (DataManager::instance()->isEnableUsbGroup()) {
// 必须确保 devlist 的生命周期长于 vGroupData 的使用周期。
// 如果 devlist 在 vGroupData 使用完毕前被释放，将导致悬空指针，引发崩溃。
// 好在 vGroupData 只在本函数中使用，不会在其他地方被引用，所以不会导致悬空指针问题。
groupNum = getUSBCameraGroup(devlist, vGroupData);
qInfo() << __func__ << "groupNum:" << groupNum;
}
if (groupNum == 1) {

@sourcery-ai sourcery-ai Bot Jul 21, 2026

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issue (complexity): Consider introducing a shared CameraEntry abstraction and a single helper for camera switching so onChangeDev() handles grouped and non-grouped devices through one unified flow instead of multiple duplicated branches.

You can significantly reduce the branching/duplication in onChangeDev() by introducing a small, common abstraction over “camera entries” and a reusable helper for the switching logic. This keeps the USB grouping feature intact while simplifying the flow.

1. Unify grouped / non‑grouped access via CameraEntry

Instead of indexing into devlist and vGroupData separately inside onChangeDev(), build a flat list of “switchable cameras” and use that everywhere:

struct CameraEntry {
    const char *device;
    const char *name;
};

static QVector<CameraEntry> buildCameraListFromDevlist(v4l2_device_list_t *devlist)
{
    QVector<CameraEntry> cameras;
    cameras.reserve(devlist->num_devices);
    for (int i = 0; i < devlist->num_devices; ++i) {
        cameras.append({
            devlist->list_devices[i].device,
            devlist->list_devices[i].name
        });
    }
    return cameras;
}

static QVector<CameraEntry> buildCameraListFromGroups(
    const QVector<QPair<QString, QVector<v4l2_dev_sys_data_t *>>> &vGroupData)
{
    QVector<CameraEntry> cameras;
    cameras.reserve(vGroupData.count());
    for (int i = 0; i < vGroupData.count(); ++i) {
        auto *dev = vGroupData[i].second[0];
        cameras.append({ dev->device, dev->name });
    }
    return cameras;
}

2. Extract the switching logic into a single helper

The “toggle when there are exactly two” and “rotate/wrap otherwise” behavior is identical for grouped and non‑grouped flows. You can express it once:

static void switchToNextCamera(
    const QVector<CameraEntry> &cameras,
    const QString &currentDevice,
    bool isToggleMode,            // true for "exactly two" behavior
    videowidget *vw)              // or capture `this` in a lambda
{
    if (cameras.isEmpty()) {
        DataManager::instance()->setdevStatus(NOCAM);
        vw->showNocam();
        return;
    }

    if (isToggleMode && cameras.size() == 2) {
        // toggle: pick the other device
        for (const auto &cam : cameras) {
            if (currentDevice != cam.device) {
                if (E_OK == vw->switchCamera(cam.device, cam.name))
                    return;
            }
        }
        return;
    }

    // rotation / wrap
    if (currentDevice.isEmpty()) {
        vw->switchCamera(cameras[0].device, cameras[0].name);
        return;
    }

    for (int i = 0; i < cameras.size(); ++i) {
        if (currentDevice == cameras[i].device) {
            const int nextIdx = (i == cameras.size() - 1) ? 0 : i + 1;
            vw->switchCamera(cameras[nextIdx].device, cameras[nextIdx].name);
            return;
        }
    }
}

3. Simplify onChangeDev() to use the helpers

The existing branching on groupNum==1 / groupNum==2 and num_devices==2 can be reduced to computing the camera list and a mode flag:

void videowidget::onChangeDev()
{
    while (m_imgPrcThread->isRunning());

    QString str;
    if (devicehandler != nullptr) {
        qDebug() << "Closing v4l2 device handler";
        str = QString(devicehandler->videodevice);
        close_v4l2_device_handler();
    }

    v4l2_device_list_t *devlist = get_device_list();
    if (!devlist) {
        qWarning() << "get device list FAILED";
        return;
    }

    int groupNum = 1;
    QVector<QPair<QString, QVector<v4l2_dev_sys_data_t *>>> vGroupData;
    if (DataManager::instance()->isEnableUsbGroup()) {
        groupNum = getUSBCameraGroup(devlist, vGroupData);
        qInfo() << __func__ << "groupNum:" << groupNum;
    }

    QVector<CameraEntry> cameras;
    bool isToggleMode = false;

    if (groupNum == 1) {
        cameras = buildCameraListFromDevlist(devlist);
        isToggleMode = (devlist->num_devices == 2);
    } else {
        cameras = buildCameraListFromGroups(vGroupData);
        isToggleMode = (groupNum == 2);
    }

    switchToNextCamera(cameras, str, isToggleMode, this);
    qDebug() << "Camera device change complete";
}

This:

  • Removes duplicated loops and manual indexing into devlist / vGroupData.
  • Encapsulates the “toggle when there are exactly two” vs “rotate/wrap” behavior.
  • Keeps all existing functionality, including USB grouping and the groupNum semantics.

4. (Optional) Clarify grouping type for getUSBCameraGroup

If you later decide to clean up getUSBCameraGroup, a simple domain type will further reduce cognitive load:

struct CameraGroup {
    QString location;
    QVector<v4l2_dev_sys_data_t *> devices;
};

int videowidget::getUSBCameraGroup(
    v4l2_device_list_t *devlist,
    QVector<CameraGroup> &groups)
{
    if (!devlist) {
        qWarning() << __func__ << "devlist is NULL!";
        return 0;
    }

    for (int i = 0; i < devlist->num_devices; ++i) {
        QString location = QString(devlist->list_devices[i].location);

        int j = 0;
        for (; j < groups.size(); ++j) {
            if (location == groups[j].location)
                break;
        }

        if (j == groups.size()) {
            CameraGroup group;
            group.location = location;
            group.devices.append(&devlist->list_devices[i]);
            groups.append(group);
        } else {
            groups[j].devices.append(&devlist->list_devices[i]);
        }
    }
    return groups.size();
}

You can then adapt buildCameraListFromGroups to use QVector<CameraGroup> instead of QVector<QPair<...>> without changing behavior.

if (devlist->num_devices == 2) {
for (int i = 0 ; i < devlist->num_devices; i++) {
const char *curDev = devlist->list_devices[i].device;
if (str != curDev) {
if (E_OK == switchCamera(curDev, devlist->list_devices[i].name)) {
break;
}
}
}
}
} else {
qDebug() << "device list has not 2 devices";
if (devlist->num_devices == 0) {
DataManager::instance()->setdevStatus(NOCAM);
showNocam();
}
} else {
if (devlist->num_devices == 0) {
DataManager::instance()->setdevStatus(NOCAM);
showNocam();
}

for (int i = 0 ; i < devlist->num_devices; i++) {
QString str1 = QString(devlist->list_devices[i].device);
for (int i = 0 ; i < devlist->num_devices; i++) {
const char *curDev = devlist->list_devices[i].device;
if (str == curDev) {
if (i == devlist->num_devices - 1) {
switchCamera(devlist->list_devices[0].device, devlist->list_devices[0].name);
break;
} else {
switchCamera(devlist->list_devices[i + 1].device, devlist->list_devices[i + 1].name);
break;
}
}

if (str == str1) {
if (i == devlist->num_devices - 1) {
if (str.isEmpty()) {
switchCamera(devlist->list_devices[0].device, devlist->list_devices[0].name);
break;
} else {
switchCamera(devlist->list_devices[i + 1].device, devlist->list_devices[i + 1].name);
break;
}
}
}
} else {
if (groupNum == 2) {
for (int i = 0 ; i < vGroupData.count(); i++) {
const char *curDev = vGroupData[i].second[0]->device;
if (str != curDev) {
if (E_OK == switchCamera(curDev, vGroupData[i].second[0]->name)) {
break;
}
}
}
} else {
if (devlist->num_devices == 0) {
DataManager::instance()->setdevStatus(NOCAM);
showNocam();
}

if (str.isEmpty()) {
switchCamera(devlist->list_devices[0].device, devlist->list_devices[0].name);
break;
for (int i = 0 ; i < vGroupData.count(); i++) {
const char *curDev = vGroupData[i].second[0]->device;
if (str == curDev) {
if (i == vGroupData.count() - 1) {
switchCamera(vGroupData[0].second[0]->device, vGroupData[0].second[0]->name);
break;
} else {
switchCamera(vGroupData[i + 1].second[0]->device, vGroupData[i + 1].second[0]->name);
break;
}
}

if (str.isEmpty()) {
switchCamera(vGroupData[0].second[0]->device, vGroupData[0].second[0]->name);
break;
}
}
}
}
Expand Down Expand Up @@ -1337,6 +1387,37 @@ int videowidget::switchCamera(const char *device, const char *devName)
return ret;
}

int videowidget::getUSBCameraGroup(v4l2_device_list_t *devlist, QVector<QPair<QString, QVector<v4l2_dev_sys_data_t *>>> &vGroupData)
{
// 来自xiwo分支，根据location进行分组
// 收到建议使用 QMap<QString, QVector<v4l2_dev_sys_data_t *>> 来存储分组数据，但我们担心影响现有代码逻辑，
// 所以暂时保留 QVector<QPair<QString, QVector<v4l2_dev_sys_data_t *>>> 来存储分组数据。
if (devlist == nullptr) {
qWarning() << __func__ << "devlist is NULL!";
return 0;
}

for (int i = 0 ; i < devlist->num_devices; i++) {
QString location = QString(devlist->list_devices[i].location);

int j = 0;
for (; j < vGroupData.count(); j++) {
if (location == vGroupData.at(j).first) {
break;
}
}
if (j == vGroupData.count()) {
QVector<v4l2_dev_sys_data_t *> vList;
vList.append(&devlist->list_devices[i]);
vGroupData.append(qMakePair(location, vList));
} else {
QVector<v4l2_dev_sys_data_t *> &vlist = vGroupData[j].second;
vlist.append(&devlist->list_devices[i]);
}
}
return vGroupData.count();
}

QString videowidget::getSaveFilePrefix()
{
qDebug() << "Entering getSaveFilePrefix";
Expand Down
12 changes: 10 additions & 2 deletions src/src/videowidget.h
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Original file line number Diff line number Diff line change
@@ -1,5 +1,5 @@
// Copyright (C) 2020 ~ 2021 Uniontech Software Technology Co.,Ltd.
// SPDX-FileCopyrightText: 2023 UnionTech Software Technology Co., Ltd.
// Copyright (C) 2020 - 2026 Uniontech Software Technology Co.,Ltd.
// SPDX-FileCopyrightText: 2023 -2026 UnionTech Software Technology Co., Ltd.
//
// SPDX-License-Identifier: GPL-3.0-or-later

Expand Down Expand Up @@ -432,6 +432,14 @@ private slots:
*/
int switchCamera(const char *device, const char *devName);

/**
* @brief 获取USB摄像头分组
* @param devlist 设备列表
* @param vGroupData 分组
* @return 分组个数
*/
int getUSBCameraGroup(v4l2_device_list_t *devlist, QVector<QPair<QString, QVector<v4l2_dev_sys_data_t *>>> &vGroupData);

/**
* @brief getSaveFilePrefix
* @return UOS_ 专业版 DEEPIN_ 社区版 CAMERA_ 其他
Expand Down
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