[FFmpeg-cvslog] vp9: Add bsf to merge superframes
Ronald S. Bultje
git at videolan.org
Thu Oct 26 20:41:35 EEST 2017
ffmpeg | branch: master | Ronald S. Bultje <rsbultje at gmail.com> | Mon Feb 29 09:43:07 2016 -0500| [0cf949a01193dcf6f83fd95d46792dd94479b4e4] | committer: Mark Thompson
vp9: Add bsf to merge superframes
>From ffmpeg commit 2e6636aa87303d37b112e79f093ca39500f92364.
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=0cf949a01193dcf6f83fd95d46792dd94479b4e4
---
Changelog | 1 +
doc/bitstream_filters.texi | 4 +
libavcodec/Makefile | 1 +
libavcodec/bitstream_filters.c | 1 +
libavcodec/vp9_superframe_bsf.c | 207 ++++++++++++++++++++++++++++++++++++++++
5 files changed, 214 insertions(+)
diff --git a/Changelog b/Changelog
index 04972399fd..b3aed3cd7e 100644
--- a/Changelog
+++ b/Changelog
@@ -12,6 +12,7 @@ version <next>:
- The x86 assembler default switched from yasm to nasm, pass
--x86asmexe=yasm to configure to restore the old behavior.
- Cineform HD decoder
+- VP9 superframe split/merge bitstream filters
version 12:
diff --git a/doc/bitstream_filters.texi b/doc/bitstream_filters.texi
index 49b8a645d0..ddadd7653e 100644
--- a/doc/bitstream_filters.texi
+++ b/doc/bitstream_filters.texi
@@ -95,6 +95,10 @@ This bitstream filter passes the packets through unchanged.
@section remove_extradata
+ at section vp9_superframe
+
+Combine VP9 frames into superframes.
+
@section vp9_superframe_split
Split VP9 superframes into single frames.
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 3a55a28e27..80c572c7c4 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -772,6 +772,7 @@ OBJS-$(CONFIG_NOISE_BSF) += noise_bsf.o
OBJS-$(CONFIG_NULL_BSF) += null_bsf.o
OBJS-$(CONFIG_REMOVE_EXTRADATA_BSF) += remove_extradata_bsf.o
OBJS-$(CONFIG_TEXT2MOVSUB_BSF) += movsub_bsf.o
+OBJS-$(CONFIG_VP9_SUPERFRAME_BSF) += vp9_superframe_bsf.o
OBJS-$(CONFIG_VP9_SUPERFRAME_SPLIT_BSF) += vp9_superframe_split_bsf.o
# thread libraries
diff --git a/libavcodec/bitstream_filters.c b/libavcodec/bitstream_filters.c
index 1cea6d77af..d46fdad81b 100644
--- a/libavcodec/bitstream_filters.c
+++ b/libavcodec/bitstream_filters.c
@@ -38,6 +38,7 @@ extern const AVBitStreamFilter ff_null_bsf;
extern const AVBitStreamFilter ff_text2movsub_bsf;
extern const AVBitStreamFilter ff_noise_bsf;
extern const AVBitStreamFilter ff_remove_extradata_bsf;
+extern const AVBitStreamFilter ff_vp9_superframe_bsf;
extern const AVBitStreamFilter ff_vp9_superframe_split_bsf;
#include "libavcodec/bsf_list.c"
diff --git a/libavcodec/vp9_superframe_bsf.c b/libavcodec/vp9_superframe_bsf.c
new file mode 100644
index 0000000000..be83ba3e75
--- /dev/null
+++ b/libavcodec/vp9_superframe_bsf.c
@@ -0,0 +1,207 @@
+/*
+ * VP9 invisible (alt-ref) frame to superframe merge bitstream filter
+ * Copyright (c) 2016 Ronald S. Bultje <rsbultje at gmail.com>
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libavutil/avassert.h"
+#include "avcodec.h"
+#include "bsf.h"
+#include "get_bits.h"
+
+#define MAX_CACHE 8
+typedef struct VP9BSFContext {
+ int n_cache;
+ struct CachedBuf {
+ uint8_t *data;
+ int size;
+ } cache[MAX_CACHE];
+} VP9BSFContext;
+
+static void stats(const struct CachedBuf *in, int n_in,
+ unsigned *_max, unsigned *_sum)
+{
+ int n;
+ unsigned max = 0, sum = 0;
+
+ for (n = 0; n < n_in; n++) {
+ unsigned sz = in[n].size;
+
+ if (sz > max)
+ max = sz;
+ sum += sz;
+ }
+
+ *_max = max;
+ *_sum = sum;
+}
+
+static int merge_superframe(const struct CachedBuf *in, int n_in, AVPacket *out)
+{
+ unsigned max, sum, mag, marker, n, sz;
+ uint8_t *ptr;
+ int res;
+
+ stats(in, n_in, &max, &sum);
+ mag = av_log2(max) >> 3;
+ marker = 0xC0 + (mag << 3) + (n_in - 1);
+ sz = sum + 2 + (mag + 1) * n_in;
+ res = av_new_packet(out, sz);
+ if (res < 0)
+ return res;
+ ptr = out->data;
+ for (n = 0; n < n_in; n++) {
+ memcpy(ptr, in[n].data, in[n].size);
+ ptr += in[n].size;
+ }
+
+#define wloop(mag, wr) do { \
+ for (n = 0; n < n_in; n++) { \
+ wr; \
+ ptr += mag + 1; \
+ } \
+ } while (0)
+
+ // write superframe with marker 110[mag:2][nframes:3]
+ *ptr++ = marker;
+ switch (mag) {
+ case 0:
+ wloop(mag, *ptr = in[n].size);
+ break;
+ case 1:
+ wloop(mag, AV_WL16(ptr, in[n].size));
+ break;
+ case 2:
+ wloop(mag, AV_WL24(ptr, in[n].size));
+ break;
+ case 3:
+ wloop(mag, AV_WL32(ptr, in[n].size));
+ break;
+ }
+ *ptr++ = marker;
+ av_assert0(ptr == &out->data[out->size]);
+
+ return 0;
+}
+
+static int vp9_superframe_filter(AVBSFContext *ctx, AVPacket *out)
+{
+ GetBitContext gb;
+ VP9BSFContext *s = ctx->priv_data;
+ AVPacket *in;
+ int res, invisible, profile, marker, uses_superframe_syntax = 0, n;
+
+ res = ff_bsf_get_packet(ctx, &in);
+ if (res < 0)
+ return res;
+
+ marker = in->data[in->size - 1];
+ if ((marker & 0xe0) == 0xc0) {
+ int nbytes = 1 + ((marker >> 3) & 0x3);
+ int n_frames = 1 + (marker & 0x7), idx_sz = 2 + n_frames * nbytes;
+
+ uses_superframe_syntax = in->size >= idx_sz && in->data[in->size - idx_sz] == marker;
+ }
+
+ if ((res = init_get_bits8(&gb, in->data, in->size)) < 0)
+ goto done;
+
+ get_bits(&gb, 2); // frame marker
+ profile = get_bits1(&gb);
+ profile |= get_bits1(&gb) << 1;
+ if (profile == 3) profile += get_bits1(&gb);
+
+ if (get_bits1(&gb)) {
+ invisible = 0;
+ } else {
+ get_bits1(&gb); // keyframe
+ invisible = !get_bits1(&gb);
+ }
+
+ if (uses_superframe_syntax && s->n_cache > 0) {
+ av_log(ctx, AV_LOG_ERROR,
+ "Mixing of superframe syntax and naked VP9 frames not supported");
+ res = AVERROR(ENOSYS);
+ goto done;
+ } else if ((!invisible || uses_superframe_syntax) && !s->n_cache) {
+ // passthrough
+ av_packet_move_ref(out, in);
+ goto done;
+ } else if (s->n_cache + 1 >= MAX_CACHE) {
+ av_log(ctx, AV_LOG_ERROR,
+ "Too many invisible frames");
+ res = AVERROR_INVALIDDATA;
+ goto done;
+ }
+
+ if (invisible) {
+ s->cache[s->n_cache].data = av_malloc(in->size);
+ if (!s->cache[s->n_cache].data) {
+ res = AVERROR(ENOMEM);
+ goto done;
+ }
+ memcpy(s->cache[s->n_cache].data, in->data, in->size);
+ s->cache[s->n_cache++].size = in->size;
+ res = AVERROR(EAGAIN);
+ goto done;
+ }
+ av_assert0(s->n_cache > 0);
+
+ s->cache[s->n_cache].data = in->data;
+ s->cache[s->n_cache].size = in->size;
+
+ // build superframe
+ if ((res = merge_superframe(s->cache, s->n_cache + 1, out)) < 0)
+ goto done;
+
+ for (n = 0; n < s->n_cache; n++)
+ av_freep(&s->cache[n].data);
+ s->n_cache = 0;
+
+ res = av_packet_copy_props(out, in);
+ if (res < 0)
+ goto done;
+
+done:
+ if (res < 0)
+ av_packet_unref(out);
+ av_packet_free(&in);
+ return res;
+}
+
+static void vp9_superframe_close(AVBSFContext *ctx)
+{
+ VP9BSFContext *s = ctx->priv_data;
+ int n;
+
+ // free cached data
+ for (n = 0; n < s->n_cache; n++)
+ av_freep(&s->cache[n].data);
+}
+
+static const enum AVCodecID codec_ids[] = {
+ AV_CODEC_ID_VP9, AV_CODEC_ID_NONE,
+};
+
+const AVBitStreamFilter ff_vp9_superframe_bsf = {
+ .name = "vp9_superframe",
+ .priv_data_size = sizeof(VP9BSFContext),
+ .filter = vp9_superframe_filter,
+ .close = vp9_superframe_close,
+ .codec_ids = codec_ids,
+};
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