obs-studio/patches/9475.patch
Ward from fusion-voyager-3 854aa51470 update to 30.0.2
2024-02-25 22:22:58 +03:00

214 lines
5.3 KiB
Diff

From 9880ec62822d86d97491bac181329907f625b52f Mon Sep 17 00:00:00 2001
From: David Rosca <nowrep@gmail.com>
Date: Tue, 2 May 2023 13:14:18 +0200
Subject: [PATCH] libobs: Add AV1 parsing functions
One notable difference from the AVC/HEVC code is that it also inserts
the METADATA and SEQUENCE_HEADER OBUs into new_packet, otherwise the
resulting video file wouldn't play.
---
libobs/CMakeLists.txt | 2 +
libobs/cmake/legacy.cmake | 2 +
libobs/obs-av1.c | 123 ++++++++++++++++++++++++++++++++++++++
libobs/obs-av1.h | 35 +++++++++++
4 files changed, 162 insertions(+)
create mode 100644 libobs/obs-av1.c
create mode 100644 libobs/obs-av1.h
diff --git a/libobs/CMakeLists.txt b/libobs/CMakeLists.txt
index 46112abe71f9d..36a75713c001f 100644
--- a/libobs/CMakeLists.txt
+++ b/libobs/CMakeLists.txt
@@ -33,6 +33,8 @@ target_sources(
obs-audio-controls.c
obs-audio-controls.h
obs-audio.c
+ obs-av1.c
+ obs-av1.h
obs-avc.c
obs-avc.h
obs-data.c
diff --git a/libobs/cmake/legacy.cmake b/libobs/cmake/legacy.cmake
index 5f13c4c0f04ab..dd77cdfb94229 100644
--- a/libobs/cmake/legacy.cmake
+++ b/libobs/cmake/legacy.cmake
@@ -32,6 +32,8 @@ target_sources(
obs-audio.c
obs-audio-controls.c
obs-audio-controls.h
+ obs-av1.c
+ obs-av1.h
obs-avc.c
obs-avc.h
obs-data.c
diff --git a/libobs/obs-av1.c b/libobs/obs-av1.c
new file mode 100644
index 0000000000000..a015130537cf2
--- /dev/null
+++ b/libobs/obs-av1.c
@@ -0,0 +1,123 @@
+// SPDX-FileCopyrightText: 2023 David Rosca <nowrep@gmail.com>
+//
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "obs-av1.h"
+
+#include "obs.h"
+
+static inline uint64_t leb128(const uint8_t *buf, size_t size, size_t *len)
+{
+ uint64_t value = 0;
+ uint8_t leb128_byte;
+
+ *len = 0;
+
+ for (int i = 0; i < 8; i++) {
+ if (size-- < 1)
+ break;
+ (*len)++;
+ leb128_byte = buf[i];
+ value |= (leb128_byte & 0x7f) << (i * 7);
+ if (!(leb128_byte & 0x80))
+ break;
+ }
+
+ return value;
+}
+
+static inline unsigned int get_bits(uint8_t val, unsigned int n,
+ unsigned int count)
+{
+ return (val >> (8 - n - count)) & ((1 << (count - 1)) * 2 - 1);
+}
+
+static void parse_obu_header(const uint8_t *buf, size_t size, size_t *obu_start,
+ size_t *obu_size, int *obu_type)
+{
+ int extension_flag, has_size_field;
+ size_t size_len = 0;
+
+ *obu_start = 0;
+ *obu_size = 0;
+ *obu_type = 0;
+
+ if (size < 1)
+ return;
+
+ *obu_type = get_bits(*buf, 1, 4);
+ extension_flag = get_bits(*buf, 5, 1);
+ has_size_field = get_bits(*buf, 6, 1);
+
+ if (extension_flag)
+ (*obu_start)++;
+
+ (*obu_start)++;
+
+ if (has_size_field)
+ *obu_size = (size_t)leb128(buf + *obu_start, size - *obu_start,
+ &size_len);
+ else
+ *obu_size = size - 1;
+
+ *obu_start += size_len;
+}
+
+bool obs_av1_keyframe(const uint8_t *data, size_t size)
+{
+ const uint8_t *start = data, *end = data + size;
+
+ while (start < end) {
+ size_t obu_start, obu_size;
+ int obu_type;
+ parse_obu_header(start, end - start, &obu_start, &obu_size,
+ &obu_type);
+
+ if (obu_size) {
+ if (obu_type == OBS_OBU_FRAME ||
+ obu_type == OBS_OBU_FRAME_HEADER) {
+ uint8_t val = *(start + obu_start);
+ if (!get_bits(val, 0, 1)) // show_existing_frame
+ return get_bits(val, 1, 2) ==
+ 0; // frame_type
+ return false;
+ }
+ }
+
+ start += obu_start + obu_size;
+ }
+
+ return false;
+}
+
+void obs_extract_av1_headers(const uint8_t *packet, size_t size,
+ uint8_t **new_packet_data, size_t *new_packet_size,
+ uint8_t **header_data, size_t *header_size)
+{
+ DARRAY(uint8_t) new_packet;
+ DARRAY(uint8_t) header;
+ const uint8_t *start = packet, *end = packet + size;
+
+ da_init(new_packet);
+ da_init(header);
+
+ while (start < end) {
+ size_t obu_start, obu_size;
+ int obu_type;
+ parse_obu_header(start, end - start, &obu_start, &obu_size,
+ &obu_type);
+
+ if (obu_type == OBS_OBU_METADATA ||
+ obu_type == OBS_OBU_SEQUENCE_HEADER) {
+ da_push_back_array(header, start, obu_start + obu_size);
+ }
+ da_push_back_array(new_packet, start, obu_start + obu_size);
+
+ start += obu_start + obu_size;
+ }
+
+ *new_packet_data = new_packet.array;
+ *new_packet_size = new_packet.num;
+ *header_data = header.array;
+ *header_size = header.num;
+}
diff --git a/libobs/obs-av1.h b/libobs/obs-av1.h
new file mode 100644
index 0000000000000..031299da0a415
--- /dev/null
+++ b/libobs/obs-av1.h
@@ -0,0 +1,35 @@
+// SPDX-FileCopyrightText: 2023 David Rosca <nowrep@gmail.com>
+//
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include "util/c99defs.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+enum {
+ OBS_OBU_SEQUENCE_HEADER = 1,
+ OBS_OBU_TEMPORAL_DELIMITER = 2,
+ OBS_OBU_FRAME_HEADER = 3,
+ OBS_OBU_TILE_GROUP = 4,
+ OBS_OBU_METADATA = 5,
+ OBS_OBU_FRAME = 6,
+ OBS_OBU_REDUNDANT_FRAME_HEADER = 7,
+ OBS_OBU_TILE_LIST = 8,
+ OBS_OBU_PADDING = 15,
+};
+
+/* Helpers for parsing AV1 OB units. */
+
+EXPORT bool obs_av1_keyframe(const uint8_t *data, size_t size);
+EXPORT void obs_extract_av1_headers(const uint8_t *packet, size_t size,
+ uint8_t **new_packet_data,
+ size_t *new_packet_size,
+ uint8_t **header_data, size_t *header_size);
+
+#ifdef __cplusplus
+}
+#endif