[3/5] libdav1d: use a custom picture allocator

Message ID 20190315224400.216-3-jamrial@gmail.com
State New
Headers show
Series
  • Untitled series #180
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Commit Message

James Almer March 15, 2019, 10:43 p.m.
Replaces the libdav1d internal allocator. It uses an AVBufferPool to reduce the
amount of allocated buffers.
About 5% speed up when decoding 720p or higher streams.
---
 libavcodec/libdav1d.c | 60 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)

Comments

Luca Barbato March 22, 2019, 9:47 p.m. | #1
On 15/03/2019 23:43, James Almer wrote:
> Replaces the libdav1d internal allocator. It uses an AVBufferPool to reduce the
> amount of allocated buffers.
> About 5% speed up when decoding 720p or higher streams.
> ---
>   libavcodec/libdav1d.c | 60 +++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 60 insertions(+)
> 

Seems fine to me.

Patch

diff --git a/libavcodec/libdav1d.c b/libavcodec/libdav1d.c
index bb7d404e7..4c93e4b7c 100644
--- a/libavcodec/libdav1d.c
+++ b/libavcodec/libdav1d.c
@@ -24,6 +24,7 @@ 
 #include "libavutil/avassert.h"
 #include "libavutil/common.h"
 #include "libavutil/internal.h"
+#include "libavutil/imgutils.h"
 #include "libavutil/opt.h"
 
 #include "avcodec.h"
@@ -33,6 +34,8 @@ 
 typedef struct Libdav1dContext {
     AVClass *class;
     Dav1dContext *c;
+    AVBufferPool *pool;
+    int pool_size;
 
     Dav1dData data;
     int tile_threads;
@@ -53,6 +56,59 @@  static void libdav1d_log_callback(void *opaque, const char *fmt, va_list vl)
     av_vlog(c, AV_LOG_ERROR, fmt, vl);
 }
 
+static int libdav1d_picture_allocator(Dav1dPicture *p, void *cookie)
+{
+    Libdav1dContext *dav1d = cookie;
+    enum AVPixelFormat format = pix_fmt[p->p.layout][p->seq_hdr->hbd];
+    int ret, linesize[4], h = FFALIGN(p->p.h, 128);
+    uint8_t *aligned_ptr, *data[4];
+    AVBufferRef *buf;
+
+    ret = av_image_fill_arrays(data, linesize, NULL, format, FFALIGN(p->p.w, 128),
+                               h, DAV1D_PICTURE_ALIGNMENT);
+    if (ret < 0)
+        return ret;
+
+    if (ret != dav1d->pool_size) {
+        av_buffer_pool_uninit(&dav1d->pool);
+        // Use twice the amount of required padding bytes for aligned_ptr below.
+        dav1d->pool = av_buffer_pool_init(ret + DAV1D_PICTURE_ALIGNMENT * 2, NULL);
+        if (!dav1d->pool)
+            return AVERROR(ENOMEM);
+        dav1d->pool_size = ret;
+    }
+    buf = av_buffer_pool_get(dav1d->pool);
+    if (!buf)
+        return AVERROR(ENOMEM);
+
+    // libdav1d requires DAV1D_PICTURE_ALIGNMENT aligned buffers, which av_malloc()
+    // doesn't guarantee for example when AVX is disabled at configure time.
+    // Use the extra DAV1D_PICTURE_ALIGNMENT padding bytes in the buffer to align it
+    // if required.
+    aligned_ptr = (uint8_t *)FFALIGN((uintptr_t)buf->data, DAV1D_PICTURE_ALIGNMENT);
+    ret = av_image_fill_pointers(data, format, h, aligned_ptr, linesize);
+    if (ret < 0) {
+        av_buffer_unref(&buf);
+        return ret;
+    }
+
+    p->data[0] = data[0];
+    p->data[1] = data[1];
+    p->data[2] = data[2];
+    p->stride[0] = linesize[0];
+    p->stride[1] = linesize[1];
+    p->allocator_data = buf;
+
+    return 0;
+}
+
+static void libdav1d_picture_release(Dav1dPicture *p, void *cookie)
+{
+    AVBufferRef *buf = p->allocator_data;
+
+    av_buffer_unref(&buf);
+}
+
 static av_cold int libdav1d_init(AVCodecContext *c)
 {
     Libdav1dContext *dav1d = c->priv_data;
@@ -64,6 +120,9 @@  static av_cold int libdav1d_init(AVCodecContext *c)
     dav1d_default_settings(&s);
     s.logger.cookie = c;
     s.logger.callback = libdav1d_log_callback;
+    s.allocator.cookie = dav1d;
+    s.allocator.alloc_picture_callback = libdav1d_picture_allocator;
+    s.allocator.release_picture_callback = libdav1d_picture_release;
     s.n_tile_threads = dav1d->tile_threads;
     s.apply_grain = dav1d->apply_grain;
     s.n_frame_threads = FFMIN(c->thread_count ? c->thread_count : av_cpu_count(), DAV1D_MAX_FRAME_THREADS);
@@ -219,6 +278,7 @@  static av_cold int libdav1d_close(AVCodecContext *c)
 {
     Libdav1dContext *dav1d = c->priv_data;
 
+    av_buffer_pool_uninit(&dav1d->pool);
     dav1d_data_unref(&dav1d->data);
     dav1d_close(&dav1d->c);