ffmpeg_bridge: new shared library isolating all FFmpeg access behind a pure C API

The library lives outside of app/ and is the only component that includes FFmpeg headers or links FFmpeg libraries. All objects (frames, packets, decoder/encoder instances, scalers, resamplers, audio filter graphs) are identified by opaque handles and never leave the library. Public surface (include/ffmpeg_bridge/ffmpeg_bridge.h): - FBFrame/FBPacket: AVFrame/AVPacket wrappers with field accessors - FBDecoder: demux+decode instance with hwaccel fallback logic - FBProbe: file probing, per-stream details, subtitle reading - FBScaler/FBResampler/FBAudioGraph: swscale/swresample/avfilter wrappers - FBEncoder: full export encoder (video filter graph, audio resampling, subtitles) ported from FFmpegEncoder - FB_* constants mirror AV_* values, verified by static_asserts against the real FFmpeg headers inside the library Two small bugs in the ported encoder were fixed: the resampler is now properly freed with swr_free() (was re-initialized with swr_init() and leaked), and codec option dictionaries are freed after avcodec_open2().
2026-07-15 22:07:57 +08:00
parent 0f41620a0b
commit ddb2b30cf4
13 changed files with 3749 additions and 0 deletions
@@ -0,0 +1,94 @@
+/***
+
+  Olive - Non-Linear Video Editor
+  Copyright (C) 2022 Olive Team
+  Modifications Copyright (C) 2025 mikesolar
+
+  This program is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This program 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 General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+***/
+
+#include "internal.h"
+
+struct FBScaler {
+	SwsContext *ctx;
+};
+
+FBScaler *fb_scaler_create(int src_width, int src_height, int src_format,
+						   int dst_width, int dst_height, int dst_format,
+						   int flags)
+{
+	SwsContext *ctx = sws_getContext(
+		src_width, src_height, static_cast<AVPixelFormat>(src_format),
+		dst_width, dst_height, static_cast<AVPixelFormat>(dst_format), flags,
+		nullptr, nullptr, nullptr);
+	if (!ctx) {
+		return nullptr;
+	}
+
+	FBScaler *s = new FBScaler;
+	s->ctx = ctx;
+	return s;
+}
+
+void fb_scaler_free(FBScaler **scaler)
+{
+	if (scaler && *scaler) {
+		sws_freeContext((*scaler)->ctx);
+		delete *scaler;
+		*scaler = nullptr;
+	}
+}
+
+int fb_scaler_set_colorspace(FBScaler *scaler, int colorspace, int jpeg_range)
+{
+	if (!scaler) {
+		return AVERROR(EINVAL);
+	}
+
+	const int *coeffs = sws_getCoefficients(
+		fb::SwsColorspaceFromAVColorSpace(static_cast<AVColorSpace>(colorspace)));
+	return sws_setColorspaceDetails(scaler->ctx, coeffs, jpeg_range, coeffs,
+									jpeg_range, 0, 0x10000, 0x10000);
+}
+
+int fb_scaler_scale_frame(FBScaler *scaler, FBFrame *dst, const FBFrame *src)
+{
+	if (!scaler || !dst || !src) {
+		return AVERROR(EINVAL);
+	}
+	return sws_scale_frame(scaler->ctx, dst->frame, src->frame);
+}
+
+int fb_scaler_scale_slices(FBScaler *scaler, const uint8_t *const *src_data,
+						   const int *src_linesize, int src_height,
+						   uint8_t *const *dst_data, const int *dst_linesize)
+{
+	if (!scaler) {
+		return AVERROR(EINVAL);
+	}
+	return sws_scale(scaler->ctx, src_data, src_linesize, 0, src_height,
+					 dst_data, dst_linesize);
+}
+
+void fb_get_yuv_coefficients(int colorspace, double out[4])
+{
+	const int *coeffs = sws_getCoefficients(
+		fb::SwsColorspaceFromAVColorSpace(static_cast<AVColorSpace>(colorspace)));
+	// Matches the historical usage order: crv, cbu, cgu, cgv
+	out[0] = coeffs[0] / 65536.0; // crv
+	out[1] = coeffs[1] / 65536.0; // cbu
+	out[2] = coeffs[2] / 65536.0; // cgu
+	out[3] = coeffs[3] / 65536.0; // cgv
+}