diff --git a/device/buffer_lock.c b/device/buffer_lock.c
index a028af2..cccae11 100644
--- a/device/buffer_lock.c
+++ b/device/buffer_lock.c
@@ -42,7 +42,6 @@ bool buffer_lock_needs_buffer(buffer_lock_t *buf_lock)
 void buffer_lock_capture(buffer_lock_t *buf_lock, buffer_t *buf)
 {
   uint64_t now = get_monotonic_time_us(NULL, NULL);
-  uint64_t captured_time_us = buf ? get_time_us(CLOCK_FROM_PARAMS, NULL, &buf->v4l2_buffer.timestamp, 0) : 0;
 
   pthread_mutex_lock(&buf_lock->lock);
   if (!buf) {
@@ -55,7 +54,7 @@ void buffer_lock_capture(buffer_lock_t *buf_lock, buffer_t *buf)
     E_LOG_DEBUG(buf_lock, "Dropped buffer %s (refs=%d), frame=%d/%d, frame_ms=%.1f",
       dev_name(buf), buf ? buf->mmap_reflinks : 0,
       buf_lock->counter, buf_lock->dropped,
-      (now - captured_time_us) / 1000.0f);
+      (now - buf->captured_time_us) / 1000.0f);
   } else {
     buffer_consumed(buf_lock->buf, buf_lock->name);
     buffer_use(buf);
@@ -64,7 +63,7 @@ void buffer_lock_capture(buffer_lock_t *buf_lock, buffer_t *buf)
     E_LOG_DEBUG(buf_lock, "Captured buffer %s (refs=%d), frame=%d/%d, processing_ms=%.1f, frame_ms=%.1f",
       dev_name(buf), buf ? buf->mmap_reflinks : 0,
       buf_lock->counter, buf_lock->dropped,
-      (now - captured_time_us) / 1000.0f,
+      (now - buf->captured_time_us) / 1000.0f,
       (now - buf_lock->buf_time_us) / 1000.0f);
     buf_lock->buf_time_us = now;
     pthread_cond_broadcast(&buf_lock->cond_wait);
diff --git a/device/hw/buffer.c b/device/hw/buffer.c
index 1218e49..bdc8029 100644
--- a/device/hw/buffer.c
+++ b/device/hw/buffer.c
@@ -14,33 +14,38 @@ buffer_t *buffer_open(const char *name, buffer_list_t *buf_list, int index) {
   buf->mmap_reflinks = 1;
   buf->used = 0;
 
-  buf->v4l2_buffer.type = buf_list->v4l2.type;
-  buf->v4l2_buffer.index = index;
+  struct v4l2_buffer v4l2_buf = {0};
+  struct v4l2_plane v4l2_plane = {0};
+
+	v4l2_buf.type = buf_list->v4l2.type;
+  v4l2_buf.index = index;
 
   if (buf_list->v4l2.do_mplanes) {
-    buf->v4l2_buffer.length = 1;
-    buf->v4l2_buffer.m.planes = &buf->v4l2_plane;
-    buf->v4l2_plane.data_offset = 0;
+    v4l2_buf.length = 1;
+    v4l2_buf.m.planes = &v4l2_plane;
+    v4l2_plane.data_offset = 0;
   }
 
   if (buf_list->do_mmap) {
-    buf->v4l2_buffer.memory = V4L2_MEMORY_MMAP;
+    v4l2_buf.memory = V4L2_MEMORY_MMAP;
   } else {
-    buf->v4l2_buffer.memory = V4L2_MEMORY_DMABUF;
+    v4l2_buf.memory = V4L2_MEMORY_DMABUF;
   }
 
-  E_XIOCTL(buf_list, dev->fd, VIDIOC_QUERYBUF, &buf->v4l2_buffer, "Cannot query buffer %d", index);
+  E_XIOCTL(buf_list, dev->fd, VIDIOC_QUERYBUF, &v4l2_buf, "Cannot query buffer %d", index);
+
+  uint64_t mem_offset = 0;
 
   if (buf_list->v4l2.do_mplanes) {
-    buf->offset = buf->v4l2_plane.m.mem_offset;
-    buf->length = buf->v4l2_plane.length;
+    mem_offset = v4l2_plane.m.mem_offset;
+    buf->length = v4l2_plane.length;
   } else {
-    buf->offset = buf->v4l2_buffer.m.offset;
-    buf->length = buf->v4l2_buffer.length;
+    mem_offset = v4l2_buf.m.offset;
+    buf->length = v4l2_buf.length;
   }
 
   if (buf_list->do_mmap) {
-    buf->start = mmap(NULL, buf->length, PROT_READ | PROT_WRITE, MAP_SHARED, dev->fd, buf->offset);
+    buf->start = mmap(NULL, buf->length, PROT_READ | PROT_WRITE, MAP_SHARED, dev->fd, mem_offset);
     if (buf->start == MAP_FAILED) {
       goto error;
     }
@@ -48,7 +53,7 @@ buffer_t *buffer_open(const char *name, buffer_list_t *buf_list, int index) {
 
   if (buf_list->do_dma) {
     struct v4l2_exportbuffer v4l2_exp = {0};
-    v4l2_exp.type = buf_list->v4l2.type;
+    v4l2_exp.type = v4l2_buf.type;
     v4l2_exp.index = index;
     v4l2_exp.plane = 0;
     E_XIOCTL(buf_list, dev->fd, VIDIOC_EXPBUF, &v4l2_exp, "Can't export queue buffer=%u to DMA", index);
diff --git a/device/hw/buffer.h b/device/hw/buffer.h
index 9b40d6f..4505746 100644
--- a/device/hw/buffer.h
+++ b/device/hw/buffer.h
@@ -12,18 +12,22 @@ typedef struct buffer_s {
   char *name;
   struct buffer_list_s *buf_list;
   int index;
+
+  // Mapped memory (with DMA)
   void *start;
-  size_t offset;
   size_t used;
   size_t length;
-  struct v4l2_buffer v4l2_buffer;
-  struct v4l2_plane v4l2_plane;
   int dma_fd;
 
+  struct {
+    unsigned flags;
+  } v4l2;
+
+  // State
   int mmap_reflinks;
-  buffer_t *mmap_source;
+  buffer_t *dma_source;
   bool enqueued;
-  uint64_t enqueue_time_us;
+  uint64_t enqueue_time_us, captured_time_us;
 } buffer_t;
 
 buffer_t *buffer_open(const char *name, buffer_list_t *buf_list, int buffer);
diff --git a/device/hw/buffer_list.c b/device/hw/buffer_list.c
index 3c4f758..6e961d7 100644
--- a/device/hw/buffer_list.c
+++ b/device/hw/buffer_list.c
@@ -229,37 +229,3 @@ int buffer_list_set_stream(buffer_list_t *buf_list, bool do_on)
 error:
   return -1;
 }
-
-int buffer_list_refresh_states(buffer_list_t *buf_list)
-{
-  if (!buf_list) {
-    return -1;
-  }
-
-  struct v4l2_buffer v4l2_buf = {0};
-  struct v4l2_plane v4l2_plane = {0};
-
-	v4l2_buf.type = buf_list->v4l2.type;
-
-  if (buf_list->v4l2.do_mplanes) {
-    v4l2_buf.length = 1;
-    v4l2_buf.m.planes = &v4l2_plane;
-  }
-
-  if (buf_list->do_mmap) {
-    v4l2_buf.memory = V4L2_MEMORY_MMAP;
-  } else {
-    v4l2_buf.memory = V4L2_MEMORY_DMABUF;
-  }
-
-  for (int i = 0; i < buf_list->nbufs; i++) {
-    v4l2_buf.index = i;
-
-  	E_XIOCTL(buf_list, buf_list->device->fd, VIDIOC_QUERYBUF, &v4l2_buf, "Can't query buffer (flags=%08x)", i);
-    E_LOG_INFO(buf_list, "Buffer: %d, Flags: %08x. Offset: %d", i, v4l2_buf.flags,
-      buf_list->v4l2.do_mplanes ? v4l2_plane.m.mem_offset : v4l2_buf.m.offset);
-  }
-
-error:
-  return -1;
-}
\ No newline at end of file
diff --git a/device/hw/buffer_list.h b/device/hw/buffer_list.h
index c9da521..8d0541e 100644
--- a/device/hw/buffer_list.h
+++ b/device/hw/buffer_list.h
@@ -42,4 +42,3 @@ buffer_t *buffer_list_find_slot(buffer_list_t *buf_list);
 buffer_t *buffer_list_dequeue(buffer_list_t *buf_list);
 int buffer_list_count_enqueued(buffer_list_t *buf_list);
 int buffer_list_enqueue(buffer_list_t *buf_list, buffer_t *dma_buf);
-int buffer_list_refresh_states(buffer_list_t *buf_list);
diff --git a/device/hw/buffer_queue.c b/device/hw/buffer_queue.c
index c555f86..fb99723 100644
--- a/device/hw/buffer_queue.c
+++ b/device/hw/buffer_queue.c
@@ -37,26 +37,57 @@ bool buffer_consumed(buffer_t *buf, const char *who)
   buf->mmap_reflinks--;
 
   if (!buf->enqueued && buf->mmap_reflinks == 0) {
+    struct v4l2_buffer v4l2_buf = {0};
+    struct v4l2_plane v4l2_plane = {0};
+
+    v4l2_buf.type = buf->buf_list->v4l2.type;
+    v4l2_buf.index = buf->index;
+    v4l2_buf.flags = buf->v4l2.flags;
+
+    if (buf->buf_list->do_mmap) {
+      assert(buf->dma_source == NULL);
+      v4l2_buf.memory = V4L2_MEMORY_MMAP;
+    } else {
+      assert(buf->dma_source != NULL);
+      v4l2_buf.memory = V4L2_MEMORY_DMABUF;
+    }
+
     // update used bytes
     if (buf->buf_list->v4l2.do_mplanes) {
-      buf->v4l2_plane.bytesused = buf->used;
-      buf->v4l2_plane.length = buf->length;
-      buf->v4l2_plane.data_offset = 0;
+      v4l2_buf.length = 1;
+      v4l2_buf.m.planes = &v4l2_plane;
+      v4l2_plane.bytesused = buf->used;
+      v4l2_plane.length = buf->length;
+      v4l2_plane.data_offset = 0;
+
+      if (buf->dma_source) {
+        assert(!buf->buf_list->do_mmap);
+        v4l2_plane.m.fd = buf->dma_source->dma_fd;
+      }
     } else {
-      buf->v4l2_buffer.bytesused = buf->used;
+      v4l2_buf.bytesused = buf->used;
+
+      if (buf->dma_source) {
+        assert(!buf->buf_list->do_mmap);
+        v4l2_buf.m.fd = buf->dma_source->dma_fd;
+      }
     }
 
     E_LOG_DEBUG(buf, "Queuing buffer... used=%zu length=%zu (linked=%s) by %s",
       buf->used,
       buf->length,
-      buf->mmap_source ? buf->mmap_source->name : NULL,
+      buf->dma_source ? buf->dma_source->name : NULL,
       who);
 
+    // Assign or clone timestamp
     if (buf->buf_list->do_timestamps) {
-      get_monotonic_time_us(NULL, &buf->v4l2_buffer.timestamp);
+      get_monotonic_time_us(NULL, &v4l2_buf.timestamp);
+    } else {
+      v4l2_buf.timestamp.tv_sec = buf->captured_time_us / (1000LL * 1000LL);
+      v4l2_buf.timestamp.tv_usec = buf->captured_time_us % (1000LL * 1000LL);
     }
 
-    E_XIOCTL(buf, buf->buf_list->device->fd, VIDIOC_QBUF, &buf->v4l2_buffer, "Can't queue buffer.");
+    E_XIOCTL(buf, buf->buf_list->device->fd, VIDIOC_QBUF, &v4l2_buf, "Can't queue buffer.");
     buf->enqueued = true;
     buf->enqueue_time_us = buf->buf_list->last_enqueued_us = get_monotonic_time_us(NULL, NULL);
   }
@@ -66,13 +97,13 @@ bool buffer_consumed(buffer_t *buf, const char *who)
 
 error:
   {
-    buffer_t *mmap_source = buf->mmap_source;
-    buf->mmap_source = NULL;
+    buffer_t *dma_source = buf->dma_source;
+    buf->dma_source = NULL;
     buf->mmap_reflinks++;
     pthread_mutex_unlock(&buffer_lock);
 
-    if (mmap_source) {
-      buffer_consumed(mmap_source, who);
+    if (dma_source) {
+      buffer_consumed(dma_source, who);
     }
   }
 
@@ -117,11 +148,10 @@ int buffer_list_enqueue(buffer_list_t *buf_list, buffer_t *dma_buf)
     return 0;
   }
 
-  // V4L2_BUF_FLAG_LAST
-  buf->v4l2_buffer.flags = 0;
-  buf->v4l2_buffer.flags &= ~V4L2_BUF_FLAG_KEYFRAME;
-  buf->v4l2_buffer.flags |= dma_buf->v4l2_buffer.flags & V4L2_BUF_FLAG_KEYFRAME;
-  buf->v4l2_buffer.timestamp = dma_buf->v4l2_buffer.timestamp;
+  buf->v4l2.flags = 0;
+  buf->v4l2.flags &= ~V4L2_BUF_FLAG_KEYFRAME;
+  buf->v4l2.flags |= dma_buf->v4l2.flags & V4L2_BUF_FLAG_KEYFRAME;
+  buf->captured_time_us = dma_buf->captured_time_us;
 
   if (buf_list->do_mmap) {
     if (dma_buf->used > buf->length) {
@@ -137,16 +167,10 @@ int buffer_list_enqueue(buffer_list_t *buf_list, buffer_t *dma_buf)
     E_LOG_DEBUG(buf, "mmap copy: dest=%p, src=%p (%s), size=%zu, space=%zu, time=%dllus",
       buf->start, dma_buf->start, dma_buf->name, dma_buf->used, buf->length, after-before);
   } else {
-    if (buf_list->v4l2.do_mplanes) {
-      buf->v4l2_plane.m.fd = dma_buf->dma_fd;
-    } else {
-      buf->v4l2_buffer.m.fd = dma_buf->dma_fd;
-    }
-
     E_LOG_DEBUG(buf, "dmabuf copy: dest=%p, src=%p (%s, dma_fd=%d), size=%zu",
       buf->start, dma_buf->start, dma_buf->name, dma_buf->dma_fd, dma_buf->used);
 
-    buf->mmap_source = dma_buf;
+    buf->dma_source = dma_buf;
     buf->length = dma_buf->length;
     dma_buf->mmap_reflinks++;
   }
@@ -179,8 +203,9 @@ buffer_t *buffer_list_dequeue(buffer_list_t *buf_list)
   } else {
     buf->used = v4l2_buf.bytesused;
   }
-  buf->v4l2_buffer.flags = v4l2_buf.flags;
-  buf->v4l2_buffer.timestamp = v4l2_buf.timestamp;
+  // TODO: Copy flags
+  buf->v4l2.flags = v4l2_buf.flags;
+  buf->captured_time_us = get_time_us(CLOCK_FROM_PARAMS, NULL, &v4l2_buf.timestamp, 0);
   buf_list->last_dequeued_us = get_monotonic_time_us(NULL, NULL);
 
   if (buf->mmap_reflinks > 0) {
@@ -195,13 +220,13 @@ buffer_t *buffer_list_dequeue(buffer_list_t *buf_list)
     buf->length,
     buf->used,
     buf_list->frames,
-    buf->mmap_source ? buf->mmap_source->name : NULL,
-    buf->v4l2_buffer.flags);
+    buf->dma_source ? buf->dma_source->name : NULL,
+    buf->v4l2.flags);
 
-  if (buf->mmap_source) {
-    buf->mmap_source->used = 0;
-    buffer_consumed(buf->mmap_source, "mmap-dequeued");
-    buf->mmap_source = NULL;
+  if (buf->dma_source) {
+    buf->dma_source->used = 0;
+    buffer_consumed(buf->dma_source, "mmap-dequeued");
+    buf->dma_source = NULL;
   }
 
   buf_list->frames++;
@@ -218,11 +243,12 @@ int buffer_list_pollfd(buffer_list_t *buf_list, struct pollfd *pollfd, bool can_
   // Can something be dequeued?
   pollfd->fd = buf_list->device->fd;
   pollfd->events = POLLHUP;
-  if (count_enqueued > 0 && can_dequeue)
+  if (count_enqueued > 0 && can_dequeue) {
     if (buf_list->do_capture)
       pollfd->events |= POLLIN;
     else
       pollfd->events |= POLLOUT;
+  }
   pollfd->revents = 0;
   return 0;
 }
diff --git a/device/v4l2/buffer.c b/device/v4l2/buffer.c
new file mode 100644
index 0000000..d5e7f97
--- /dev/null
+++ b/device/v4l2/buffer.c
@@ -0,0 +1,38 @@
+#include "device/v4l2/v4l2.h"
+#include "device/hw/v4l2.h"
+#include "device/hw/buffer_list.h"
+#include "device/hw/device.h"
+
+int buffer_list_v4l2_refresh_states(buffer_list_t *buf_list)
+{
+  if (!buf_list) {
+    return -1;
+  }
+
+  struct v4l2_buffer v4l2_buf = {0};
+  struct v4l2_plane v4l2_plane = {0};
+
+	v4l2_buf.type = buf_list->v4l2.type;
+
+  if (buf_list->v4l2.do_mplanes) {
+    v4l2_buf.length = 1;
+    v4l2_buf.m.planes = &v4l2_plane;
+  }
+
+  if (buf_list->do_mmap) {
+    v4l2_buf.memory = V4L2_MEMORY_MMAP;
+  } else {
+    v4l2_buf.memory = V4L2_MEMORY_DMABUF;
+  }
+
+  for (int i = 0; i < buf_list->nbufs; i++) {
+    v4l2_buf.index = i;
+
+  	E_XIOCTL(buf_list, buf_list->device->fd, VIDIOC_QUERYBUF, &v4l2_buf, "Can't query buffer (flags=%08x)", i);
+    E_LOG_INFO(buf_list, "Buffer: %d, Flags: %08x. Offset: %d", i, v4l2_buf.flags,
+      buf_list->v4l2.do_mplanes ? v4l2_plane.m.mem_offset : v4l2_buf.m.offset);
+  }
+
+error:
+  return -1;
+}
diff --git a/device/v4l2/v4l2.h b/device/v4l2/v4l2.h
new file mode 100644
index 0000000..d2b7667
--- /dev/null
+++ b/device/v4l2/v4l2.h
@@ -0,0 +1,5 @@
+#pragma once
+
+typedef struct buffer_list_s buffer_list_t;
+
+int buffer_list_v4l2_refresh_states(buffer_list_t *buf_list);
diff --git a/http/http_h264.c b/http/http_h264.c
index 9dacbc5..57eae72 100644
--- a/http/http_h264.c
+++ b/http/http_h264.c
@@ -53,7 +53,7 @@ bool h264_is_key_frame(buffer_t *buf)
   unsigned char *data = buf->start;
   device_t *camera = buf->buf_list->device;
 
-  if (buf->v4l2_buffer.flags & V4L2_BUF_FLAG_KEYFRAME) {
+  if (buf->v4l2.flags & V4L2_BUF_FLAG_KEYFRAME) {
     E_LOG_DEBUG(buf, "Got key frame (from V4L2)!");
     return true;
   } else if (buf->used >= 5 && (data[4] & 0x1F) == 0x07) {