Add support NV21 preview callback

o always force to use YV12 for gralloc buffer, regardless preview color format (NV21 or YV12)
o for NV21 preview callback, a color conversion is performed before the preview frame is returned via the callback

Change-Id: I7e5fb4de40e5f615585465f9b9c50eb3521c1c57
related-to-bug: 5121691,5122253

1 files changed, 45 insertions, 114 deletions

diff --git a/libcamera/SecCameraHWInterface.cpp b/libcamera/SecCameraHWInterface.cpp
index c316ea6..34f1009 100644
--- a/libcamera/SecCameraHWInterface.cpp
+++ b/libcamera/SecCameraHWInterface.cpp
@@ -39,22 +39,18 @@
 #define BACK_CAMERA_INFINITY_FOCUS_DISTANCES_STR   "0.10,1.20,Infinity"
 #define FRONT_CAMERA_FOCUS_DISTANCES_STR           "0.20,0.25,Infinity"
 
-// This hack does two things:
-// -- it sets preview to NV21 (YUV420SP)
-// -- it sets gralloc to YV12
+// FIXME:
+// -- The actual preview color is set to YV12. The preview frames
+//    returned via preview callback must be generated by color
+//    conversion if the requested preview color format for the
+//    preview frames is _not_ YV12. The reason that YV12 is used
+//    for actual preview is because that is the only color format
+//    supported by gralloc. Matching the preview cor format with
+//    gralloc color format improves performance since no color
+//    conversion is needed for preview.
 //
-// The reason being: the samsung encoder understands only yuv420sp, and gralloc
-// does yv12 and rgb565.  So what we do is we break up the interleaved UV in
-// separate V and U planes, which makes preview look good, and enabled the
-// encoder as well.
-//
-// FIXME: Samsung needs to enable support for proper yv12 coming out of the
-//        camera, and to fix their video encoder to work with yv12.
-// FIXME: It also seems like either Samsung's YUV420SP (NV21) or img's YV12 has
-//        the color planes switched.  We need to figure which side is doing it
-//        wrong and have the respective party fix it.
-
-#define HACK 0
+// -- we only support two preview color formats that client
+//    applications can set: NV21 and YUV420/YV12.
 
 namespace android {
 
@@ -181,20 +177,13 @@ void CameraHardwareSec::initDefaultParameters(int cameraId)
                                        &snapshot_max_height) < 0)
         LOGE("getSnapshotMaxSize fail (%d / %d) \n",
              snapshot_max_width, snapshot_max_height);
-
-//  p.setPreviewFormat(CameraParameters::PIXEL_FORMAT_RGB565);
-//  p.set(CameraParameters::KEY_SUPPORTED_PREVIEW_FORMATS, CameraParameters::PIXEL_FORMAT_RGB565);
-//  p.set(CameraParameters::KEY_VIDEO_FRAME_FORMAT, CameraParameters::PIXEL_FORMAT_RGB565);
-#if HACK
+    String8 previewColorString;
+    previewColorString = CameraParameters::PIXEL_FORMAT_YUV420SP;
+    previewColorString.append(",");
+    previewColorString.append(CameraParameters::PIXEL_FORMAT_YUV420P);
     p.setPreviewFormat(CameraParameters::PIXEL_FORMAT_YUV420SP); mFrameSizeDelta = 16;
-    p.set(CameraParameters::KEY_SUPPORTED_PREVIEW_FORMATS, CameraParameters::PIXEL_FORMAT_YUV420SP);
-    p.set(CameraParameters::KEY_VIDEO_FRAME_FORMAT, CameraParameters::PIXEL_FORMAT_YUV420SP);
-#else
-    p.setPreviewFormat(CameraParameters::PIXEL_FORMAT_YUV420P); mFrameSizeDelta = 16;
-    p.set(CameraParameters::KEY_SUPPORTED_PREVIEW_FORMATS, CameraParameters::PIXEL_FORMAT_YUV420P);
+    p.set(CameraParameters::KEY_SUPPORTED_PREVIEW_FORMATS, previewColorString.string());
     p.set(CameraParameters::KEY_VIDEO_FRAME_FORMAT, CameraParameters::PIXEL_FORMAT_YUV420P);
-#endif
-//  p.setPreviewFormat(CameraParameters::PIXEL_FORMAT_YUV420P); mFrameSizeDelta = 16;
     p.setPreviewSize(preview_max_width, preview_max_height);
 
     p.setPictureFormat(CameraParameters::PIXEL_FORMAT_JPEG);
@@ -411,36 +400,12 @@ status_t CameraHardwareSec::setPreviewWindow(preview_stream_ops *w)
     int preview_width;
     int preview_height;
     mParameters.getPreviewSize(&preview_width, &preview_height);
-
-    int hal_pixel_format;
+    int hal_pixel_format = HAL_PIXEL_FORMAT_YV12;
 
     const char *str_preview_format = mParameters.getPreviewFormat();
     LOGV("%s: preview format %s", __func__, str_preview_format);
     mFrameSizeDelta = 16;
 
-    hal_pixel_format = HAL_PIXEL_FORMAT_YV12; // default
-
-    if (!strcmp(str_preview_format,
-                CameraParameters::PIXEL_FORMAT_RGB565)) {
-        hal_pixel_format = HAL_PIXEL_FORMAT_RGB_565;
-        mFrameSizeDelta = 0;
-    }
-    else if (!strcmp(str_preview_format,
-                     CameraParameters::PIXEL_FORMAT_RGBA8888)) {
-        hal_pixel_format = HAL_PIXEL_FORMAT_RGBA_8888;
-        mFrameSizeDelta = 0;
-    }
-    else if (!strcmp(str_preview_format,
-                     CameraParameters::PIXEL_FORMAT_YUV420SP)) {
-#if HACK
-        hal_pixel_format = HAL_PIXEL_FORMAT_YV12;
-#else
-        hal_pixel_format = HAL_PIXEL_FORMAT_YCrCb_420_SP;
-#endif
-    } else if (!strcmp(str_preview_format,
-                     CameraParameters::PIXEL_FORMAT_YUV420P))
-        hal_pixel_format = HAL_PIXEL_FORMAT_YV12; // HACK
-
     if (w->set_usage(w, GRALLOC_USAGE_SW_WRITE_OFTEN)) {
         LOGE("%s: could not set usage on gralloc buffer", __func__);
         return INVALID_OPERATION;
@@ -601,7 +566,7 @@ int CameraHardwareSec::previewThread()
             char *frame = ((char *)mPreviewHeap->data) + offset;
             int total = frame_size + mFrameSizeDelta;
 
-// HACK or no HACK, the code below assumes YUV, not RGB
+            // the code below assumes YUV, not RGB
             {
                 int h;
                 char *src = frame;
@@ -614,40 +579,7 @@ int CameraHardwareSec::previewThread()
                     src += width;
                 }
 
-                if (HACK) {
-                    // The incoming data is in NV21 format, and we need to
-                    // convert it to YV12 for the gralloc buffer.
-
-                    char *uv = src;
-                    const int uv_size = width * height / 2;
-                    char saved_uv[uv_size];
-                    memcpy(saved_uv, src, uv_size);
-
-                    // first, collapse the V chroma pixels into their own plane
-                    // following the Y plane.
-                    h = 0;
-                    while (h < width * height / 4) {
-                        *ptr++ = *src;
-                        src += 2;
-                        h++;
-                        if (!(h % (width / 2)))
-                            ptr += (stride - width) / 2;
-                    }
-
-                    // next, use the saved_uv plane and collapse the U chroma
-                    // pixels into their own plane following the newly-created
-                    // V plane.
-                    h = 0;
-                    src = saved_uv + 1;
-                    while (h < width * height / 4) {
-                        *ptr++ = *src;
-                        src += 2;
-                        h++;
-                        if (!(h % (width / 2)))
-                            ptr += (stride - width) / 2;
-                    }
-                }
-                else {
+                {
                     // U
                     char *v = ptr;
                     ptr += stride * height / 4;
@@ -679,8 +611,26 @@ int CameraHardwareSec::previewThread()
 
 callbacks:
     // Notify the client of a new frame.
-    if (mMsgEnabled & CAMERA_MSG_PREVIEW_FRAME)
+    if (mMsgEnabled & CAMERA_MSG_PREVIEW_FRAME) {
+        const char * preview_format = mParameters.getPreviewFormat();
+        if (!strcmp(preview_format, CameraParameters::PIXEL_FORMAT_YUV420SP)) {
+            // Color conversion from YUV420 to NV21
+            char *vu = ((char *)mPreviewHeap->data) + offset + width * height;
+            const int uv_size = (width * height) >> 1;
+            char saved_uv[uv_size];
+            memcpy(saved_uv, vu, uv_size);
+            char *u = saved_uv;
+            char *v = u + (uv_size >> 1);
+
+            int h = 0;
+            while (h < width * height / 4) {
+                *vu++ = *v++;
+                *vu++ = *u++;
+                ++h;
+            }
+        }
         mDataCb(CAMERA_MSG_PREVIEW_FRAME, mPreviewHeap, index, NULL, mCallbackCookie);
+    }
 
     Mutex::Autolock lock(mRecordLock);
     if (mRecordRunning == true) {
@@ -1615,36 +1565,17 @@ status_t CameraHardwareSec::setParameters(const CameraParameters& params)
     LOGV("%s : new_preview_width x new_preview_height = %dx%d, format = %s",
          __func__, new_preview_width, new_preview_height, new_str_preview_format);
 
+    if (strcmp(new_str_preview_format, CameraParameters::PIXEL_FORMAT_YUV420SP) &&
+        strcmp(new_str_preview_format, CameraParameters::PIXEL_FORMAT_YUV420P)) {
+        LOGE("Unsupported preview color format: %s", new_str_preview_format);
+        return BAD_VALUE;
+    }
+
     if (0 < new_preview_width && 0 < new_preview_height &&
             new_str_preview_format != NULL &&
             isSupportedPreviewSize(new_preview_width, new_preview_height)) {
-        int new_preview_format = 0;
-
+        int new_preview_format = V4L2_PIX_FMT_YUV420;
         mFrameSizeDelta = 16;
-        if (!strcmp(new_str_preview_format,
-                    CameraParameters::PIXEL_FORMAT_RGB565)) {
-            new_preview_format = V4L2_PIX_FMT_RGB565;
-            mFrameSizeDelta = 0;
-        }
-        else if (!strcmp(new_str_preview_format,
-                         CameraParameters::PIXEL_FORMAT_RGBA8888)) {
-            new_preview_format = V4L2_PIX_FMT_RGB32;
-            mFrameSizeDelta = 0;
-        }
-        else if (!strcmp(new_str_preview_format,
-                         CameraParameters::PIXEL_FORMAT_YUV420SP))
-            new_preview_format = V4L2_PIX_FMT_NV21;
-        else if (!strcmp(new_str_preview_format,
-                         CameraParameters::PIXEL_FORMAT_YUV420P))
-            new_preview_format = V4L2_PIX_FMT_YUV420;
-        else if (!strcmp(new_str_preview_format, "yuv420sp_custom"))
-            new_preview_format = V4L2_PIX_FMT_NV12T;
-        else if (!strcmp(new_str_preview_format, "yuv422i"))
-            new_preview_format = V4L2_PIX_FMT_YUYV;
-        else if (!strcmp(new_str_preview_format, "yuv422p"))
-            new_preview_format = V4L2_PIX_FMT_YUV422P;
-        else
-            new_preview_format = V4L2_PIX_FMT_NV21; //for 3rd party
 
         int current_preview_width, current_preview_height, current_frame_size;
         mSecCamera->getPreviewSize(&current_preview_width,