Changeset 3634 for pjproject/branches/projects/2.0-dev

Timestamp:

Jul 13, 2011 8:51:10 AM (13 years ago)

Author:

nanang

Message:

Re #1263:

• Renamed API pjsua_call_set_vid_out() with pjsua_call_set_vid_strm().
• Implemented initial version of the function, features covered:
  • add, remove video media stream during the call
  • change which device to use during the call
  • start/stop video stream transmission

Location:

pjproject/branches/projects/2.0-dev

Files:

• pjsip-apps/src/pjsua/pjsua_app.c (modified) (3 diffs)
• pjsip/include/pjsua-lib/pjsua.h (modified) (2 diffs)
• pjsip/include/pjsua-lib/pjsua_internal.h (modified) (1 diff)
• pjsip/src/pjsua-lib/pjsua_media.c (modified) (2 diffs)
• pjsip/src/pjsua-lib/pjsua_vid.c (modified) (6 diffs)

pjproject/branches/projects/2.0-dev/pjsip-apps/src/pjsua/pjsua_app.c

@@ -1452 +1452 @@
             cur_acc->vid_in_auto_show = PJ_TRUE;
             cur_acc->vid_out_auto_transmit = PJ_TRUE;
-            PJ_TODO(implement_pjsua_option_for_vid_auto_show_transmit);
+            PJ_TODO(implement_pjsua_option_for_vid_auto_show_and_transmit);
             break;
         case OPT_EXTRA_AUDIO:
@@ -3316 +3316 @@
     puts("| vid call rx on|off        Enable/disable incoming video for current call    |");
     puts("| vid call tx on|off        Enable/disable video tx for current call          |");
+    puts("| vid call add              Add video stream for current call                 |");
+    puts("| vid call remove [idx]     Remove video stream #idx for current call         |");
     puts("| vid dev list              List all video devices                            |");
     puts("| vid dev refresh           Refresh video device list                         |");
@@ -3754 +3756 @@
         vid_show_help();
     } else if (strcmp(argv[1], "call")==0) {
+        pjsua_call_vid_strm_op_param param;
         pj_bool_t tx = (strcmp(argv[2], "tx") == 0);
-        pj_bool_t on = (strcmp(argv[3], "on") == 0);
-
+        if (tx) {
+            pj_bool_t on = (strcmp(argv[3], "on") == 0);
+        }
+
+        if (strcmp(argv[2], "add")==0) {
+            pjsua_call_set_vid_strm(current_call, PJSUA_CALL_VID_STRM_ADD, NULL);
+        }
+        if (strcmp(argv[2], "remove")==0) {
+            param.med_idx = argc >= 4? atoi(argv[3]) : -1;
+            pjsua_call_set_vid_strm(current_call, PJSUA_CALL_VID_STRM_REMOVE, &param);
+        }
         PJ_TODO(vid_enable_disable_video_on_call);
         PJ_LOG(1,(THIS_FILE, "Not implemented"));

pjproject/branches/projects/2.0-dev/pjsip/include/pjsua-lib/pjsua.h

@@ -368 +368 @@
 
 } pjsua_state;
+
+
+/**
+ * This enumeration represents video stream operation on a call.
+ * See also #pjsua_call_vid_strm_op_param for further info.
+ */
+typedef enum pjsua_call_vid_strm_op
+{
+    /**
+     * Add a new video stream.
+     */
+    PJSUA_CALL_VID_STRM_ADD,
+
+    /**
+     * Remove an existing video stream.
+     */
+    PJSUA_CALL_VID_STRM_REMOVE,
+
+    /**
+     * Modify an existing video stream, such as changing the capture device.
+     */
+    PJSUA_CALL_VID_STRM_MODIFY,
+
+    /**
+     * Start transmitting video stream.
+     */
+    PJSUA_CALL_VID_STRM_START_TRANSMIT,
+
+    /**
+     * Stop transmitting video stream.
+     */
+    PJSUA_CALL_VID_STRM_STOP_TRANSMIT,
+
+} pjsua_call_vid_strm_op;
+
+
+/**
+ * Parameters for video stream operation on a call.
+ */
+typedef struct pjsua_call_vid_strm_op_param
+{
+    /**
+     * Specify the media stream index. This can be set to -1 to denote
+     * the default video stream in the call, which is the first active
+     * video stream or any first video stream if none is active.
+     *
+     * This field is valid for all video stream operations, except
+     * PJSUA_CALL_VID_STRM_ADD.
+     */
+    int med_idx;
+ 
+    /**
+     * Specify the video capture device ID. This can be set to
+     * PJMEDIA_VID_DEFAULT_CAPTURE_DEV to specify the default capture
+     * device as configured in the account.
+     *
+     * This field is valid for the following video stream operations:
+     * PJSUA_CALL_VID_STRM_ADD, PJSUA_CALL_VID_STRM_MODIFY, and
+     * PJSUA_CALL_VID_STRM_START_TRANSMIT.
+     */
+    pjmedia_vid_dev_index cap_dev;
+
+} pjsua_call_vid_strm_op_param;
 
 
@@ -3681 +3744 @@
 PJ_DECL(int) pjsua_call_get_vid_stream_idx(pjsua_call_id call_id);
 
-/**
- * Start, stop, and/or manipulate video transmission for the specified
- * call. This would trigger a re-INVITE or UPDATE to be sent for the
- * call. This function may add, remove, or modify existing video media
- * stream, depending on the media index specified (the \a med_idx argument).
- *
- * To add a new or edit existing video stream (for transmission), specify
- * a valid video capture device ID or PJMEDIA_VID_DEFAULT_CAPTURE_DEV in
- * the \a cap_dev argument. If \a med_idx is set to default stream (-1),
- * then the function will modify existing video stream if one exists, or
- * add a new one if it doesn't. If \a med_idx is set to a specific stream
- * index, the function will modify that video stream. Otherwise if \a med_idx
- * is set to value larger than the current media count, a new video stream
- * will be added to the call.
- *
- * To remove an existing video stream, specify PJMEDIA_VID_INVALID_DEV in
- * \a cap_dev argument. If \a med_idx is set to default stream (-1), this
- * will remove the default/first video stream in the call, otherwise
- * application can put a specific value to request removal of that particular
- * video stream.
+
+/**
+ * Add, remove, modify, and/or manipulate video media stream for the
+ * specified call. This may trigger a re-INVITE or UPDATE to be sent
+ * for the call.
  *
  * @param call_id       Call identification.
- * @param med_idx       The media stream index. Currently the value MUST
- *                      be -1 to denote the default video stream in the
- *                      call.
- * @param cap_dev       To add or modify existing video media stream,
- *                      specify PJMEDIA_VID_DEFAULT_CAPTURE_DEV to use
- *                      the default capture device as configured in the
- *                      account, or specify a specific capture device ID.
- *                      To disable an existing video stream, specify
- *                      PJMEDIA_VID_INVALID_DEV for this parameter.
+ * @param op            The video stream operation to be performed,
+ *                      possible values are #pjsua_call_vid_strm_op.
+ * @param param         The parameters for the video stream operation.
  *
  * @return              PJ_SUCCESS on success or the appropriate error.
  */
-PJ_DECL(pj_status_t) pjsua_call_set_vid_out(pjsua_call_id call_id,
-                                            int med_idx,
-                                            pjmedia_vid_dev_index cap_dev);
+PJ_DECL(pj_status_t) pjsua_call_set_vid_strm (
+                                pjsua_call_id call_id,
+                                pjsua_call_vid_strm_op op,
+                                const pjsua_call_vid_strm_op_param *param);
+
 
 /**

pjproject/branches/projects/2.0-dev/pjsip/include/pjsua-lib/pjsua_internal.h

@@ -75 +75 @@
             pjsua_vid_win_id     cap_win_id;/**< The video capture window   */
             pjsua_vid_win_id     rdr_win_id;/**< The video render window    */
+            pjmedia_vid_dev_index cap_dev;  /**< The video capture device   */
+            pjmedia_vid_dev_index rdr_dev;  /**< The video-in render device */
         } v;
 

pjproject/branches/projects/2.0-dev/pjsip/src/pjsua-lib/pjsua_media.c

@@ -1314 +1314 @@
 
 /* Initialize the media line */
-static pj_status_t pjsua_call_media_init(pjsua_call_media *call_med,
-                                         pjmedia_type type,
-                                         const pjsua_transport_config *tcfg,
-                                         int security_level,
-                                         int *sip_err_code)
+pj_status_t pjsua_call_media_init(pjsua_call_media *call_med,
+                                  pjmedia_type type,
+                                  const pjsua_transport_config *tcfg,
+                                  int security_level,
+                                  int *sip_err_code)
 {
     pjsua_acc *acc = &pjsua_var.acc[call_med->call->acc_id];
@@ -1343 +1343 @@
         
         call_med->tp_st = PJSUA_MED_TP_IDLE;
+
+        /* While in initial call, set default video devices */
+        if (type == PJMEDIA_TYPE_VIDEO) {
+            call_med->strm.v.rdr_dev = acc->cfg.vid_rend_dev;
+            call_med->strm.v.cap_dev = acc->cfg.vid_cap_dev;
+            if (call_med->strm.v.rdr_dev == PJMEDIA_VID_DEFAULT_RENDER_DEV) {
+                pjmedia_vid_dev_info info;
+                pjmedia_vid_dev_get_info(call_med->strm.v.rdr_dev, &info);
+                call_med->strm.v.rdr_dev = info.id;
+            }
+            if (call_med->strm.v.cap_dev == PJMEDIA_VID_DEFAULT_CAPTURE_DEV) {
+                pjmedia_vid_dev_info info;
+                pjmedia_vid_dev_get_info(call_med->strm.v.cap_dev, &info);
+                call_med->strm.v.cap_dev = info.id;
+            }
+        }
     } else if (call_med->tp_st == PJSUA_MED_TP_DISABLED) {
         /* Media is being reenabled. */

pjproject/branches/projects/2.0-dev/pjsip/src/pjsua-lib/pjsua_vid.c

@@ -608 +608 @@
 
         /* Setup decoding direction */
-        if (si->dir & PJMEDIA_DIR_DECODING) {
+        if (si->dir & PJMEDIA_DIR_DECODING)
+        {
             pjsua_vid_win_id wid;
             pjsua_vid_win *w;
@@ -621 +622 @@
             status = create_vid_win(PJSUA_WND_TYPE_STREAM,
                                     &media_port->info.fmt,
-                                    acc->cfg.vid_rend_dev,
+                                    call_med->strm.v.rdr_dev,
+                                    //acc->cfg.vid_rend_dev,
                                     PJSUA_INVALID_ID,
                                     acc->cfg.vid_in_auto_show,
@@ -647 +649 @@
 
         /* Setup encoding direction */
-        if (si->dir & PJMEDIA_DIR_ENCODING && !call->local_hold &&
-            acc->cfg.vid_out_auto_transmit)
+        if (si->dir & PJMEDIA_DIR_ENCODING && !call->local_hold)
         {
             pjsua_vid_win *w;
@@ -662 +663 @@
             status = create_vid_win(PJSUA_WND_TYPE_PREVIEW,
                                     &media_port->info.fmt,
-                                    acc->cfg.vid_rend_dev,
-                                    acc->cfg.vid_cap_dev,
+                                    call_med->strm.v.rdr_dev,
+                                    call_med->strm.v.cap_dev,
+                                    //acc->cfg.vid_rend_dev,
+                                    //acc->cfg.vid_cap_dev,
                                     PJ_FALSE,
                                     &wid);
@@ -737 +740 @@
     }
 
+    if (acc->cfg.vid_out_auto_transmit) {
+        status = pjmedia_vid_stream_pause(call_med->strm.v.stream,
+                                          PJMEDIA_DIR_ENCODING);
+        if (status != PJ_SUCCESS)
+            return status;
+    }
+
     return PJ_SUCCESS;
 }
@@ -1007 +1017 @@
 
 
+static void call_get_vid_strm_info(pjsua_call *call,
+                                   int *first_active,
+                                   int *first_inactive,
+                                   unsigned *active_cnt,
+                                   unsigned *cnt)
+{
+    unsigned i, var_cnt = 0;
+
+    if (first_active && ++var_cnt)
+        *first_active = -1;
+    if (first_inactive && ++var_cnt)
+        *first_inactive = -1;
+    if (active_cnt && ++var_cnt)
+        *active_cnt = 0;
+    if (cnt && ++var_cnt)
+        *cnt = 0;
+
+    for (i = 0; i < call->med_cnt && var_cnt; ++i) {
+        if (call->media[i].type == PJMEDIA_TYPE_VIDEO) {
+            if (call->media[i].dir != PJMEDIA_DIR_NONE)
+            {
+                if (first_active && *first_active == -1) {
+                    *first_active = i;
+                    --var_cnt;
+                }
+                if (active_cnt)
+                    ++(*active_cnt);
+            } else if (first_inactive && *first_inactive == -1) {
+                *first_inactive = i;
+                --var_cnt;
+            }
+            if (cnt)
+                ++(*cnt);
+        }
+    }
+}
+
+
+/* Send SDP reoffer. */
+static pj_status_t call_reoffer_sdp(pjsua_call_id call_id,
+                                    const pjmedia_sdp_session *sdp)
+{
+    pjsua_call *call;
+    pjsip_tx_data *tdata;
+    pjsip_dialog *dlg;
+    pj_status_t status;
+
+    status = acquire_call("call_reoffer_sdp()", call_id, &call, &dlg);
+    if (status != PJ_SUCCESS)
+        return status;
+
+    if (call->inv->state != PJSIP_INV_STATE_CONFIRMED) {
+        PJ_LOG(3,(THIS_FILE, "Can not re-INVITE call that is not confirmed"));
+        pjsip_dlg_dec_lock(dlg);
+        return PJSIP_ESESSIONSTATE;
+    }
+
+    /* Create re-INVITE with new offer */
+    status = pjsip_inv_reinvite( call->inv, NULL, sdp, &tdata);
+    if (status != PJ_SUCCESS) {
+        pjsua_perror(THIS_FILE, "Unable to create re-INVITE", status);
+        pjsip_dlg_dec_lock(dlg);
+        return status;
+    }
+
+    /* Send the request */
+    status = pjsip_inv_send_msg( call->inv, tdata);
+    if (status != PJ_SUCCESS) {
+        pjsua_perror(THIS_FILE, "Unable to send re-INVITE", status);
+        pjsip_dlg_dec_lock(dlg);
+        return status;
+    }
+
+    pjsip_dlg_dec_lock(dlg);
+
+    return PJ_SUCCESS;
+}
+
+
+pj_status_t pjsua_call_media_init(pjsua_call_media *call_med,
+                                  pjmedia_type type,
+                                  const pjsua_transport_config *tcfg,
+                                  int security_level,
+                                  int *sip_err_code);
+
+
+/* Add a new video stream into a call */
+static pj_status_t call_add_video(pjsua_call *call,
+                                  pjmedia_vid_dev_index cap_dev)
+{
+    pj_pool_t *pool = call->inv->pool_prov;
+    pjsua_acc_config *acc_cfg = &pjsua_var.acc[call->acc_id].cfg;
+    pjsua_call_media *call_med;
+    pjmedia_sdp_session *sdp;
+    pjmedia_sdp_media *sdp_m;
+    pjmedia_transport_info tpinfo;
+    pjmedia_vid_dev_info vinfo;
+    unsigned active_cnt;
+    pj_status_t status;
+
+    /* Verify media slot availability */
+    if (call->med_cnt == PJSUA_MAX_CALL_MEDIA)
+        return PJ_ETOOMANY;
+
+    call_get_vid_strm_info(call, NULL, NULL, &active_cnt, NULL);
+    if (active_cnt == acc_cfg->max_video_cnt)
+        return PJ_ETOOMANY;
+
+    /* Verify the capture device */
+    status = pjmedia_vid_dev_get_info(cap_dev, &vinfo);
+    if (status != PJ_SUCCESS)
+        return status;
+
+    if (vinfo.dir != PJMEDIA_DIR_CAPTURE)
+        return PJ_EINVAL;
+
+    cap_dev = vinfo.id;
+
+    /* Get active local SDP */
+    status = pjmedia_sdp_neg_get_active_local(call->inv->neg, &sdp);
+    if (status != PJ_SUCCESS)
+        return status;
+
+    /* Initialize call media */
+    call_med = &call->media[call->med_cnt++];
+
+    status = pjsua_call_media_init(call_med, PJMEDIA_TYPE_VIDEO,
+                                   &acc_cfg->rtp_cfg, call->secure_level,
+                                   NULL);
+    if (status != PJ_SUCCESS)
+        goto on_error;
+
+    /* Override default capture device setting */
+    call_med->strm.v.cap_dev = cap_dev;
+
+    /* Init transport media */
+    status = pjmedia_transport_media_create(call_med->tp, pool, 0,
+                                            NULL, call_med->idx);
+    if (status != PJ_SUCCESS)
+        goto on_error;
+
+    call_med->tp_st = PJSUA_MED_TP_INIT;
+
+    /* Get transport address info */
+    pjmedia_transport_info_init(&tpinfo);
+    pjmedia_transport_get_info(call_med->tp, &tpinfo);
+
+    /* Create SDP media line */
+    status = pjmedia_endpt_create_video_sdp(pjsua_var.med_endpt, pool,
+                                            &tpinfo.sock_info, 0, &sdp_m);
+    if (status != PJ_SUCCESS)
+        goto on_error;
+
+    sdp->media[sdp->media_count++] = sdp_m;
+
+    /* Update SDP media line by media transport */
+    status = pjmedia_transport_encode_sdp(call_med->tp, pool,
+                                          sdp, NULL, call_med->idx);
+    if (status != PJ_SUCCESS)
+        goto on_error;
+
+    status = call_reoffer_sdp(call->index, sdp);
+    if (status != PJ_SUCCESS)
+        goto on_error;
+
+    return PJ_SUCCESS;
+
+on_error:
+    if (call_med->tp) {
+        pjmedia_transport_close(call_med->tp);
+        call_med->tp = call_med->tp_orig = NULL;
+    }
+
+    return status;
+}
+
+
+/* Remove a video stream from a call */
+static pj_status_t call_remove_video(pjsua_call *call,
+                                     int med_idx)
+{
+    pjsua_call_media *call_med;
+    pjmedia_sdp_session *sdp;
+    pj_status_t status;
+
+    /* Verify and normalize media index */
+    if (med_idx == -1) {
+        int first_active;
+        
+        call_get_vid_strm_info(call, &first_active, NULL, NULL, NULL);
+        if (first_active == -1)
+            return PJ_ENOTFOUND;
+
+        med_idx = first_active;
+    }
+
+    call_med = &call->media[med_idx];
+
+    /* Verify if the stream media type is video */
+    if (call_med->type != PJMEDIA_TYPE_VIDEO)
+        return PJ_EINVAL;
+
+    /* Verify if the stream already disabled */
+    if (call_med->dir != PJMEDIA_DIR_NONE)
+        return PJ_SUCCESS;
+
+    /* Mark media transport to disabled */
+    // Don't close this here, as SDP negotiation has not been
+    // done and stream may be still active.
+    call_med->tp_st = PJSUA_MED_TP_DISABLED;
+
+    /* Get active local SDP */
+    status = pjmedia_sdp_neg_get_active_local(call->inv->neg, &sdp);
+    if (status != PJ_SUCCESS)
+        return status;
+
+    pj_assert(med_idx < (int)sdp->media_count);
+    sdp->media[med_idx]->desc.port = 0;
+
+    status = call_reoffer_sdp(call->index, sdp);
+    if (status != PJ_SUCCESS)
+        return status;
+
+    return PJ_SUCCESS;
+}
+
+
+/* Modify a video stream in a call */
+static pj_status_t call_modify_video(pjsua_call *call,
+                                     int med_idx,
+                                     pjmedia_vid_dev_index cap_dev)
+{
+    pjsua_call_media *call_med;
+    pjmedia_vid_dev_info info;
+    pjsua_vid_win *w, *new_w = NULL;
+    pjsua_vid_win_id wid, new_wid;
+    pjmedia_port *media_port;
+    pj_status_t status;
+
+    /* Verify and normalize media index */
+    if (med_idx == -1) {
+        int first_active;
+        
+        call_get_vid_strm_info(call, &first_active, NULL, NULL, NULL);
+        if (first_active == -1)
+            return PJ_ENOTFOUND;
+
+        med_idx = first_active;
+    }
+
+    call_med = &call->media[med_idx];
+
+    /* Verify if the stream media type is video */
+    if (call_med->type != PJMEDIA_TYPE_VIDEO)
+        return PJ_EINVAL;
+
+    /* Verify the capture device */
+    status = pjmedia_vid_dev_get_info(cap_dev, &info);
+    if (status != PJ_SUCCESS)
+        return status;
+
+    if (info.dir != PJMEDIA_DIR_CAPTURE)
+        return PJ_EINVAL;
+
+    cap_dev = info.id;
+
+    /* The specified capture device is being used already */
+    if (call_med->strm.v.cap_dev == cap_dev)
+        return PJ_SUCCESS;
+
+    /* == Apply the new capture device == */
+
+    wid = call_med->strm.v.cap_win_id;
+    w = &pjsua_var.win[wid];
+    pj_assert(w->type == PJSUA_WND_TYPE_PREVIEW && w->vp_cap);
+
+    status = pjmedia_vid_stream_get_port(call_med->strm.v.stream,
+                                         PJMEDIA_DIR_ENCODING, &media_port);
+    if (status != PJ_SUCCESS)
+        return status;
+    
+    /* = Detach stream port from the old capture device = */
+    status = pjmedia_vid_port_disconnect(w->vp_cap);
+    if (status != PJ_SUCCESS)
+        return status;
+
+    status = pjmedia_vid_tee_remove_dst_port(w->tee, media_port);
+    if (status != PJ_SUCCESS) {
+        /* Connect back the old capturer */
+        pjmedia_vid_port_connect(w->vp_cap, media_port, PJ_FALSE);
+        return status;
+    }
+
+    /* = Attach stream port to the new capture device = */
+
+    /* Create preview video window */
+    status = create_vid_win(PJSUA_WND_TYPE_PREVIEW,
+                            &media_port->info.fmt,
+                            call_med->strm.v.rdr_dev,
+                            cap_dev,
+                            PJ_FALSE,
+                            &new_wid);
+    if (status != PJ_SUCCESS)
+        goto on_error;
+
+    inc_vid_win(new_wid);
+    new_w = &pjsua_var.win[new_wid];
+    
+    /* Connect stream to capturer (via video window tee) */
+    status = pjmedia_vid_tee_add_dst_port2(new_w->tee, 0, media_port);
+    if (status != PJ_SUCCESS)
+        goto on_error;
+
+    /* Connect capturer to tee */
+    status = pjmedia_vid_port_connect(new_w->vp_cap, new_w->tee, PJ_FALSE);
+    if (status != PJ_SUCCESS)
+        return status;
+
+    /* Start renderer */
+    status = pjmedia_vid_port_start(new_w->vp_rend);
+    if (status != PJ_SUCCESS)
+        goto on_error;
+
+    /* Start capturer */
+    status = pjmedia_vid_port_start(new_w->vp_cap);
+    if (status != PJ_SUCCESS)
+        goto on_error;
+
+    /* Finally */
+    call_med->strm.v.cap_dev = cap_dev;
+    call_med->strm.v.cap_win_id = new_wid;
+    dec_vid_win(wid);
+
+    return PJ_SUCCESS;
+
+on_error:
+    if (new_w) {
+        /* Disconnect media port from the new capturer */
+        pjmedia_vid_tee_remove_dst_port(new_w->tee, media_port);
+        /* Release the new capturer */
+        dec_vid_win(new_wid);
+    }
+
+    /* Revert back to the old capturer */
+    status = pjmedia_vid_tee_add_dst_port2(w->tee, 0, media_port);
+    if (status != PJ_SUCCESS)
+        return status;
+
+    status = pjmedia_vid_port_connect(w->vp_cap, w->tee, PJ_FALSE);
+    if (status != PJ_SUCCESS)
+        return status;
+
+    return status;
+}
+
+
+/* Start transmitting video stream in a call */
+static pj_status_t call_start_tx_video(pjsua_call *call,
+                                       int med_idx,
+                                       pjmedia_vid_dev_index cap_dev)
+{
+    pjsua_call_media *call_med;
+    pj_status_t status;
+
+    /* Verify and normalize media index */
+    if (med_idx == -1) {
+        int first_active;
+        
+        call_get_vid_strm_info(call, &first_active, NULL, NULL, NULL);
+        if (first_active == -1)
+            return PJ_ENOTFOUND;
+
+        med_idx = first_active;
+    }
+
+    call_med = &call->media[med_idx];
+
+    /* Verify if the stream is transmitting video */
+    if (call_med->type != PJMEDIA_TYPE_VIDEO || 
+        (call_med->dir & PJMEDIA_DIR_ENCODING) == 0)
+    {
+        return PJ_EINVAL;
+    }
+
+    /* Apply the new capture device */
+    status = call_modify_video(call, med_idx, cap_dev);
+    if (status != PJ_SUCCESS)
+        return status;
+
+    /* Start stream in encoding direction */
+    status = pjmedia_vid_stream_resume(call_med->strm.v.stream,
+                                       PJMEDIA_DIR_ENCODING);
+    if (status != PJ_SUCCESS)
+        return status;
+
+    return PJ_SUCCESS;
+}
+
+
+/* Stop transmitting video stream in a call */
+static pj_status_t call_stop_tx_video(pjsua_call *call,
+                                      int med_idx)
+{
+    pjsua_call_media *call_med;
+    pj_status_t status;
+
+    /* Verify and normalize media index */
+    if (med_idx == -1) {
+        int first_active;
+        
+        call_get_vid_strm_info(call, &first_active, NULL, NULL, NULL);
+        if (first_active == -1)
+            return PJ_ENOTFOUND;
+
+        med_idx = first_active;
+    }
+
+    call_med = &call->media[med_idx];
+
+    /* Verify if the stream is transmitting video */
+    if (call_med->type != PJMEDIA_TYPE_VIDEO || 
+        (call_med->dir & PJMEDIA_DIR_ENCODING) == 0)
+    {
+        return PJ_EINVAL;
+    }
+
+    /* Pause stream in encoding direction */
+    status = pjmedia_vid_stream_pause( call_med->strm.v.stream,
+                                       PJMEDIA_DIR_ENCODING);
+    if (status != PJ_SUCCESS)
+        return status;
+
+    return PJ_SUCCESS;
+}
+
+
+/*
+ * Start, stop, and/or manipulate video transmission for the specified call.
+ */
+PJ_DEF(pj_status_t) pjsua_call_set_vid_strm (
+                                pjsua_call_id call_id,
+                                pjsua_call_vid_strm_op op,
+                                const pjsua_call_vid_strm_op_param *param)
+{
+    pjsua_call *call;
+    pjsua_call_vid_strm_op_param param_;
+    pj_status_t status;
+
+    PJ_ASSERT_RETURN(call_id>=0 && call_id<(int)pjsua_var.ua_cfg.max_calls,
+                     PJ_EINVAL);
+
+    PJSUA_LOCK();
+
+    call = &pjsua_var.calls[call_id];
+
+    if (param) {
+        param_ = *param;
+    } else {
+        param_.med_idx = -1;
+        param_.cap_dev = PJMEDIA_VID_DEFAULT_CAPTURE_DEV;
+    }
+
+    /* Get real capture ID, if set to PJMEDIA_VID_DEFAULT_CAPTURE_DEV */
+    if (param_.cap_dev == PJMEDIA_VID_DEFAULT_CAPTURE_DEV) {
+        pjmedia_vid_dev_info info;
+        pjmedia_vid_dev_get_info(param_.cap_dev, &info);
+        param_.cap_dev = info.id;
+    }
+
+    switch (op) {
+    case PJSUA_CALL_VID_STRM_ADD:
+        status = call_add_video(call, param_.cap_dev);
+        break;
+    case PJSUA_CALL_VID_STRM_REMOVE:
+        status = call_remove_video(call, param_.med_idx);
+        break;
+    case PJSUA_CALL_VID_STRM_MODIFY:
+        status = call_modify_video(call, param_.med_idx, param_.cap_dev);
+        break;
+    case PJSUA_CALL_VID_STRM_START_TRANSMIT:
+        status = call_start_tx_video(call, param_.med_idx, param_.cap_dev);
+        break;
+    case PJSUA_CALL_VID_STRM_STOP_TRANSMIT:
+        status = call_stop_tx_video(call, param_.med_idx);
+        break;
+    default:
+        status = PJ_EINVALIDOP;
+        break;
+    }
+
+    PJSUA_UNLOCK();
+
+    return status;
+}
+
 
 #endif /* PJSUA_HAS_VIDEO */