coremediabuffer: handle stride alignment

Handle stride alignment through the use of the video meta API. The
code is based on the corevideobuffer implementation.

If the video meta API is not supported and the underlying buffer
contains padding, the core media buffer is copied to a system memory
buffer.

https://bugzilla.gnome.org/show_bug.cgi?id=727885

sys/applemedia/avfvideosrc.m

@@ -811,7 +811,7 @@ didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
     }
   }
 
-  *buf = gst_core_media_buffer_new (sbuf);
+  *buf = gst_core_media_buffer_new (sbuf, useVideoMeta);
   CFRelease (sbuf);
 
   [self timestampBuffer:*buf];

sys/applemedia/coremediabuffer.c

@@ -1,5 +1,7 @@
 /*
  * Copyright (C) 2009 Ole André Vadla Ravnås <oleavr@soundrop.com>
+ * Copyright (C) 2014 Collabora Ltd.
+ *   Authors:    Matthieu Bouron <matthieu.bouron@collabora.com>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ -63,55 +65,190 @@ gst_core_media_meta_get_info (void)
   return core_media_meta_info;
 }
 
+static GstVideoFormat
+gst_core_media_buffer_get_video_format (OSType format)
+{
+  switch (format) {
+    case kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange:
+      return GST_VIDEO_FORMAT_NV12;
+    case kCVPixelFormatType_422YpCbCr8_yuvs:
+      return GST_VIDEO_FORMAT_YUY2;
+    case kCVPixelFormatType_422YpCbCr8:
+      return GST_VIDEO_FORMAT_UYVY;
+    case kCVPixelFormatType_32BGRA:
+      return GST_VIDEO_FORMAT_BGRA;
+    default:
+      GST_WARNING ("Unknown OSType format: %d", (gint) format);
+      return GST_VIDEO_FORMAT_UNKNOWN;
+  }
+}
+
+static gboolean
+gst_core_media_buffer_wrap_pixel_buffer (GstBuffer * buf, GstVideoInfo * info,
+    CVPixelBufferRef pixel_buf, gboolean * has_padding)
+{
+  guint n_planes;
+  gsize offset[GST_VIDEO_MAX_PLANES] = { 0 };
+  gint stride[GST_VIDEO_MAX_PLANES] = { 0 };
+  GstVideoMeta *video_meta;
+  UInt32 size;
+
+  if (CVPixelBufferLockBaseAddress (pixel_buf,
+          kCVPixelBufferLock_ReadOnly) != kCVReturnSuccess) {
+    GST_ERROR ("Could not lock pixel buffer base address");
+    return FALSE;
+  }
+
+  *has_padding = FALSE;
+
+  if (CVPixelBufferIsPlanar (pixel_buf)) {
+    gint i, size = 0, plane_offset = 0;
+
+    n_planes = CVPixelBufferGetPlaneCount (pixel_buf);
+    for (i = 0; i < n_planes; i++) {
+      stride[i] = CVPixelBufferGetBytesPerRowOfPlane (pixel_buf, i);
+
+      if (stride[i] != GST_VIDEO_INFO_PLANE_STRIDE (info, i)) {
+        *has_padding = TRUE;
+      }
+
+      size = stride[i] * CVPixelBufferGetHeightOfPlane (pixel_buf, i);
+      offset[i] = plane_offset;
+      plane_offset += size;
+
+      gst_buffer_append_memory (buf,
+          gst_memory_new_wrapped (GST_MEMORY_FLAG_NO_SHARE,
+              CVPixelBufferGetBaseAddressOfPlane (pixel_buf, i), size, 0, size,
+              NULL, NULL));
+    }
+  } else {
+
+    n_planes = 1;
+    stride[0] = CVPixelBufferGetBytesPerRow (pixel_buf);
+    offset[0] = 0;
+    size = stride[0] * CVPixelBufferGetHeight (pixel_buf);
+
+    gst_buffer_append_memory (buf,
+        gst_memory_new_wrapped (GST_MEMORY_FLAG_NO_SHARE,
+            CVPixelBufferGetBaseAddress (pixel_buf), size, 0, size, NULL,
+            NULL));
+  }
+
+  video_meta =
+      gst_buffer_add_video_meta_full (buf, GST_VIDEO_FRAME_FLAG_NONE,
+      GST_VIDEO_INFO_FORMAT (info), info->width, info->height, n_planes, offset,
+      stride);
+
+  return TRUE;
+}
+
+static gboolean
+gst_core_media_buffer_wrap_block_buffer (GstBuffer * buf,
+    CMBlockBufferRef block_buf)
+{
+  OSStatus status;
+  gchar *data = NULL;
+  UInt32 size;
+
+  status = CMBlockBufferGetDataPointer (block_buf, 0, 0, 0, &data);
+  if (status != noErr) {
+    return FALSE;
+  }
+
+  size = CMBlockBufferGetDataLength (block_buf);
+
+  gst_buffer_append_memory (buf,
+      gst_memory_new_wrapped (GST_MEMORY_FLAG_NO_SHARE, data,
+          size, 0, size, NULL, NULL));
+
+  return TRUE;
+}
+
+static GstBuffer *
+gst_core_media_buffer_new_from_buffer (GstBuffer * buf, GstVideoInfo * info)
+{
+  gboolean ret;
+  GstBuffer *copy_buf;
+  GstVideoFrame dest, src;
+  GstAllocator *allocator;
+
+  allocator = gst_allocator_find (GST_ALLOCATOR_SYSMEM);
+  if (!allocator) {
+    GST_ERROR ("Could not find SYSMEM allocator");
+    return NULL;
+  }
+
+  copy_buf = gst_buffer_new_allocate (allocator, info->size, NULL);
+
+  gst_object_unref (allocator);
+
+  if (!gst_video_frame_map (&dest, info, copy_buf, GST_MAP_WRITE)) {
+    GST_ERROR ("Could not map destination frame");
+    goto error;
+  }
+
+  if (!gst_video_frame_map (&src, info, buf, GST_MAP_READ)) {
+    GST_ERROR ("Could not map source frame");
+    gst_video_frame_unmap (&dest);
+    goto error;
+  }
+
+  ret = gst_video_frame_copy (&dest, &src);
+
+  gst_video_frame_unmap (&dest);
+  gst_video_frame_unmap (&src);
+
+  if (!ret) {
+    GST_ERROR ("Could not copy frame");
+    goto error;
+  }
+
+  return copy_buf;
+
+error:
+  if (copy_buf) {
+    gst_buffer_unref (copy_buf);
+  }
+  return NULL;
+}
+
+static gboolean
+gst_video_info_init_from_pixel_buffer (GstVideoInfo * info,
+    CVPixelBufferRef pixel_buf)
+{
+  size_t width, height;
+  OSType format_type;
+  GstVideoFormat video_format;
+
+  width = CVPixelBufferGetWidth (pixel_buf);
+  height = CVPixelBufferGetHeight (pixel_buf);
+  format_type = CVPixelBufferGetPixelFormatType (pixel_buf);
+  video_format = gst_core_media_buffer_get_video_format (format_type);
+
+  if (video_format == GST_VIDEO_FORMAT_UNKNOWN) {
+    return FALSE;
+  }
+
+  gst_video_info_init (info);
+  gst_video_info_set_format (info, video_format, width, height);
+
+  return TRUE;
+}
+
 GstBuffer *
-gst_core_media_buffer_new (CMSampleBufferRef sample_buf)
+gst_core_media_buffer_new (CMSampleBufferRef sample_buf,
+    gboolean use_video_meta)
 {
   CVImageBufferRef image_buf;
   CVPixelBufferRef pixel_buf;
   CMBlockBufferRef block_buf;
-  gchar *data = NULL;
-  UInt32 size;
-  OSStatus status;
-  GstBuffer *buf;
   GstCoreMediaMeta *meta;
+  GstBuffer *buf;
 
   image_buf = CMSampleBufferGetImageBuffer (sample_buf);
   pixel_buf = NULL;
   block_buf = CMSampleBufferGetDataBuffer (sample_buf);
 
-  if (image_buf != NULL && CFGetTypeID (image_buf) == CVPixelBufferGetTypeID ()) {
-    pixel_buf = (CVPixelBufferRef) image_buf;
-
-    if (CVPixelBufferLockBaseAddress (pixel_buf,
-            kCVPixelBufferLock_ReadOnly) != kCVReturnSuccess) {
-      goto error;
-    }
-
-    if (CVPixelBufferIsPlanar (pixel_buf)) {
-      gint plane_count, plane_idx;
-
-      data = CVPixelBufferGetBaseAddressOfPlane (pixel_buf, 0);
-
-      size = 0;
-      plane_count = CVPixelBufferGetPlaneCount (pixel_buf);
-      for (plane_idx = 0; plane_idx != plane_count; plane_idx++) {
-        size += CVPixelBufferGetBytesPerRowOfPlane (pixel_buf, plane_idx) *
-            CVPixelBufferGetHeightOfPlane (pixel_buf, plane_idx);
-      }
-    } else {
-      data = CVPixelBufferGetBaseAddress (pixel_buf);
-      size = CVPixelBufferGetBytesPerRow (pixel_buf) *
-          CVPixelBufferGetHeight (pixel_buf);
-    }
-  } else if (block_buf != NULL) {
-    status = CMBlockBufferGetDataPointer (block_buf, 0, 0, 0, &data);
-    if (status != noErr)
-      goto error;
-    size = CMBlockBufferGetDataLength (block_buf);
-  } else {
-    goto error;
-  }
-
   buf = gst_buffer_new ();
 
   meta = (GstCoreMediaMeta *) gst_buffer_add_meta (buf,
@@ -126,13 +263,49 @@ gst_core_media_buffer_new (CMSampleBufferRef sample_buf)
   meta->pixel_buf = pixel_buf;
   meta->block_buf = block_buf;
 
-  gst_buffer_append_memory (buf,
-      gst_memory_new_wrapped (GST_MEMORY_FLAG_NO_SHARE, data,
-          size, 0, size, NULL, NULL));
+  if (image_buf != NULL && CFGetTypeID (image_buf) == CVPixelBufferGetTypeID ()) {
+    GstVideoInfo info;
+    gboolean has_padding = FALSE;
+
+    pixel_buf = (CVPixelBufferRef) image_buf;
+    if (!gst_video_info_init_from_pixel_buffer (&info, pixel_buf)) {
+      goto error;
+    }
+
+    if (!gst_core_media_buffer_wrap_pixel_buffer (buf, &info, pixel_buf,
+            &has_padding)) {
+      goto error;
+    }
+
+    /* If the video meta API is not supported, remove padding by
+     * copying the core media buffer to a system memory buffer */
+    if (has_padding && !use_video_meta) {
+      GstBuffer *copy_buf;
+      copy_buf = gst_core_media_buffer_new_from_buffer (buf, &info);
+      if (!copy_buf) {
+        goto error;
+      }
+
+      gst_buffer_unref (buf);
+      buf = copy_buf;
+    }
+
+  } else if (block_buf != NULL) {
+
+    if (!gst_core_media_buffer_wrap_block_buffer (buf, block_buf)) {
+      goto error;
+    }
+
+  } else {
+    goto error;
+  }
 
   return buf;
 
 error:
+  if (buf) {
+    gst_buffer_unref (buf);
+  }
   return NULL;
 }
 

sys/applemedia/coremediabuffer.h

@@ -21,6 +21,7 @@
 #define __GST_CORE_MEDIA_BUFFER_H__
 
 #include <gst/gst.h>
+#include <gst/video/gstvideometa.h>
 
 #include "CoreMedia/CoreMedia.h"
 
@@ -41,7 +42,8 @@ typedef struct _GstCoreMediaMeta
 } GstCoreMediaMeta;
 
 
-GstBuffer * gst_core_media_buffer_new      (CMSampleBufferRef sample_buf);
+GstBuffer * gst_core_media_buffer_new      (CMSampleBufferRef sample_buf,
+                                            gboolean use_video_meta);
 CVPixelBufferRef gst_core_media_buffer_get_pixel_buffer
                                            (GstBuffer * buf);
 GType gst_core_media_meta_api_get_type (void);

sys/applemedia/vtenc.c

@@ -903,7 +903,9 @@ gst_vtenc_enqueue_buffer (void *data, int a2, int a3, int a4,
   }
   self->expect_keyframe = FALSE;
 
-  buf = gst_core_media_buffer_new (sbuf);
+  /* We are dealing with block buffers here, so we don't need
+   * to enable the use of the video meta API on the core media buffer */
+  buf = gst_core_media_buffer_new (sbuf, FALSE);
   gst_buffer_copy_into (buf, self->cur_inbuf, GST_BUFFER_COPY_TIMESTAMPS,
       0, -1);
   if (is_keyframe) {