avformat/{isom,mov,movenc}: add support for CMAF DASH roles

This information is coded in a standard MP4 KindBox and utilizes the
scheme and values as per the DASH role scheme defined in MPEG-DASH.
Other schemes are technically allowed, but where multiple schemes
define the same concepts, the DASH scheme should be utilized.

Such flagging is additionally utilized by the DASH-IF CMAF ingest
specification, enabling an encoder to inform the following component
of the roles of the incoming media streams.

A test is added for this functionality in a similar manner to the
matroska test.

Signed-off-by: Jan Ekström <jan.ekstrom@24i.com>

1 files changed, 91 insertions, 0 deletions

diff --git a/libavformat/mov.c b/libavformat/mov.c
index d0b8b2595b..a811bc7677 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -28,6 +28,7 @@
 #include <stdint.h>
 
 #include "libavutil/attributes.h"
+#include "libavutil/bprint.h"
 #include "libavutil/channel_layout.h"
 #include "libavutil/internal.h"
 #include "libavutil/intreadwrite.h"
@@ -6853,6 +6854,95 @@ static int mov_read_dvcc_dvvc(MOVContext *c, AVIOContext *pb, MOVAtom atom)
     return 0;
 }
 
+static int mov_read_kind(MOVContext *c, AVIOContext *pb, MOVAtom atom)
+{
+    AVFormatContext *ctx = c->fc;
+    AVStream *st = NULL;
+    AVBPrint scheme_buf, value_buf;
+    int64_t scheme_str_len = 0, value_str_len = 0;
+    int version, flags, ret = AVERROR_BUG;
+    int64_t size = atom.size;
+
+    if (atom.size < 6)
+        // 4 bytes for version + flags, 2x 1 byte for null
+        return AVERROR_INVALIDDATA;
+
+    if (c->fc->nb_streams < 1)
+        return 0;
+    st = c->fc->streams[c->fc->nb_streams-1];
+
+    version = avio_r8(pb);
+    flags   = avio_rb24(pb);
+    size   -= 4;
+
+    if (version != 0 || flags != 0) {
+        av_log(ctx, AV_LOG_ERROR,
+               "Unsupported 'kind' box with version %d, flags: %x",
+               version, flags);
+        return AVERROR_INVALIDDATA;
+    }
+
+    av_bprint_init(&scheme_buf, 0, AV_BPRINT_SIZE_UNLIMITED);
+    av_bprint_init(&value_buf,  0, AV_BPRINT_SIZE_UNLIMITED);
+
+    if ((scheme_str_len = ff_read_string_to_bprint_overwrite(pb, &scheme_buf,
+                                                             size)) < 0) {
+        ret = scheme_str_len;
+        goto cleanup;
+    }
+
+    if (scheme_str_len + 1 >= size) {
+        // we need to have another string, even if nullptr.
+        // we check with + 1 since we expect that if size was not hit,
+        // an additional null was read.
+        ret = AVERROR_INVALIDDATA;
+        goto cleanup;
+    }
+
+    size -= scheme_str_len + 1;
+
+    if ((value_str_len = ff_read_string_to_bprint_overwrite(pb, &value_buf,
+                                                            size)) < 0) {
+        ret = value_str_len;
+        goto cleanup;
+    }
+
+    if (value_str_len == size) {
+        // in case of no trailing null, box is not valid.
+        ret = AVERROR_INVALIDDATA;
+        goto cleanup;
+    }
+
+    av_log(ctx, AV_LOG_TRACE,
+           "%s stream %d KindBox(scheme: %s, value: %s)\n",
+           av_get_media_type_string(st->codecpar->codec_type),
+           st->index,
+           scheme_buf.str, value_buf.str);
+
+    for (int i = 0; ff_mov_track_kind_table[i].scheme_uri; i++) {
+        const struct MP4TrackKindMapping map = ff_mov_track_kind_table[i];
+        if (!av_strstart(scheme_buf.str, map.scheme_uri, NULL))
+            continue;
+
+        for (int j = 0; map.value_maps[j].disposition; j++) {
+            const struct MP4TrackKindValueMapping value_map = map.value_maps[j];
+            if (!av_strstart(value_buf.str, value_map.value, NULL))
+                continue;
+
+            st->disposition |= value_map.disposition;
+        }
+    }
+
+    ret = 0;
+
+cleanup:
+
+    av_bprint_finalize(&scheme_buf, NULL);
+    av_bprint_finalize(&value_buf,  NULL);
+
+    return ret;
+}
+
 static const MOVParseTableEntry mov_default_parse_table[] = {
 { MKTAG('A','C','L','R'), mov_read_aclr },
 { MKTAG('A','P','R','G'), mov_read_avid },
@@ -6950,6 +7040,7 @@ static const MOVParseTableEntry mov_default_parse_table[] = {
 { MKTAG('c','l','l','i'), mov_read_clli },
 { MKTAG('d','v','c','C'), mov_read_dvcc_dvvc },
 { MKTAG('d','v','v','C'), mov_read_dvcc_dvvc },
+{ MKTAG('k','i','n','d'), mov_read_kind },
 { 0, NULL }
 };