FFmpeg 7.1 + cuframes input demuxer

Snapshot FFmpeg n7.1 (release tag) с применённым patch'ем для cuframes
input format. Используется как FFMPEG_REPO_OVERRIDE в NickM-27/FFmpeg-Builds
fork для статической сборки patched binary под Frigate (Debian 12 / glibc 2.36).

Apply changes:
  + libavformat/cuframesdec.c (новый — реализация демуксера)
  M libavformat/Makefile (CONFIG_CUFRAMES_DEMUXER target)
  M libavformat/allformats.c (extern declaration)
  M configure (--enable-libcuframes option + dep check)

Patch source: https://git.goldix.org/gx/cuframes (filter/ffmpeg-7.1-cuframes-demuxer.patch)

History сброшена (snapshot вместо fork) потому что upstream shallow clone
не позволял push в gitea. Полная история FFmpeg — на github.com/FFmpeg/FFmpeg n7.1.

libavformat/mlpdec.c

@@ -0,0 +1,131 @@
+/*
+ * MLP and TrueHD demuxer
+ * Copyright (c) 2001 Fabrice Bellard
+ * Copyright (c) 2005 Alex Beregszaszi
+ * Copyright (c) 2015 Carl Eugen Hoyos
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "config_components.h"
+
+#include "avformat.h"
+#include "avio_internal.h"
+#include "demux.h"
+#include "internal.h"
+#include "rawdec.h"
+#include "libavutil/intreadwrite.h"
+#include "libavcodec/mlp.h"
+#include "libavcodec/mlp_parse.h"
+
+static int av_always_inline mlp_thd_probe(const AVProbeData *p, uint32_t sync)
+{
+    const uint8_t *buf, *last_buf = p->buf, *end = p->buf + p->buf_size;
+    int valid = 0, size = 0;
+    int nsubframes = 0;
+
+    for (buf = p->buf; buf + 8 <= end; buf++) {
+        if (AV_RB32(buf + 4) == sync) {
+            if (last_buf + size == buf) {
+                valid += 1 + nsubframes / 8;
+            }
+            nsubframes = 0;
+            last_buf = buf;
+            size = (AV_RB16(buf) & 0xfff) * 2;
+        } else if (buf - last_buf == size) {
+            nsubframes++;
+            size += (AV_RB16(buf) & 0xfff) * 2;
+        }
+    }
+    if (valid >= 100)
+        return AVPROBE_SCORE_MAX;
+    return 0;
+}
+
+static int mlp_read_header(AVFormatContext *s)
+{
+    int ret = ff_raw_audio_read_header(s);
+
+    if (ret < 0)
+        return ret;
+
+    ret = ffio_ensure_seekback(s->pb, 10);
+    if (ret == 0) {
+        uint8_t buffer[10];
+        int read, sample_rate = 0;
+
+        read = avio_read(s->pb, buffer, 10);
+        if (read == 10) {
+            switch (buffer[7]) {
+            case SYNC_TRUEHD:
+                sample_rate = mlp_samplerate(buffer[8] >> 4);
+                break;
+            case SYNC_MLP:
+                sample_rate = mlp_samplerate(buffer[9] >> 4);
+                break;
+            }
+
+            if (sample_rate)
+                avpriv_set_pts_info(s->streams[0], 64, 1, sample_rate);
+        }
+
+        if (read > 0)
+            avio_seek(s->pb, -read, SEEK_CUR);
+    }
+
+    return 0;
+}
+
+#if CONFIG_MLP_DEMUXER
+static int mlp_probe(const AVProbeData *p)
+{
+    return mlp_thd_probe(p, 0xf8726fbb);
+}
+
+const FFInputFormat ff_mlp_demuxer = {
+    .p.name         = "mlp",
+    .p.long_name    = NULL_IF_CONFIG_SMALL("raw MLP"),
+    .p.flags        = AVFMT_GENERIC_INDEX | AVFMT_NOTIMESTAMPS,
+    .p.extensions   = "mlp",
+    .p.priv_class   = &ff_raw_demuxer_class,
+    .read_probe     = mlp_probe,
+    .read_header    = mlp_read_header,
+    .read_packet    = ff_raw_read_partial_packet,
+    .raw_codec_id   = AV_CODEC_ID_MLP,
+    .priv_data_size = sizeof(FFRawDemuxerContext),
+};
+#endif
+
+#if CONFIG_TRUEHD_DEMUXER
+static int thd_probe(const AVProbeData *p)
+{
+    return mlp_thd_probe(p, 0xf8726fba);
+}
+
+const FFInputFormat ff_truehd_demuxer = {
+    .p.name         = "truehd",
+    .p.long_name    = NULL_IF_CONFIG_SMALL("raw TrueHD"),
+    .p.flags        = AVFMT_GENERIC_INDEX | AVFMT_NOTIMESTAMPS,
+    .p.extensions   = "thd",
+    .p.priv_class   = &ff_raw_demuxer_class,
+    .read_probe     = thd_probe,
+    .read_header    = mlp_read_header,
+    .read_packet    = ff_raw_read_partial_packet,
+    .raw_codec_id   = AV_CODEC_ID_TRUEHD,
+    .priv_data_size = sizeof(FFRawDemuxerContext),
+};
+#endif