[FFmpeg-devel] [PATCH v2 2/2] avformat/mov: add support for 'amve' ambient viewing environment box. As defined in ISOBMFF (ISO/IEC 14496-12) document.

Damiano Galassi damiog at gmail.com
Sun Jul 16 09:21:22 EEST 2023


---
 libavformat/dump.c   | 15 +++++++++++++++
 libavformat/isom.h   |  3 +++
 libavformat/mov.c    | 36 ++++++++++++++++++++++++++++++++++++
 libavformat/movenc.c | 22 ++++++++++++++++++++++
 4 files changed, 76 insertions(+)

diff --git a/libavformat/dump.c b/libavformat/dump.c
index d31e4c2ec6..88dc9dd89c 100644
--- a/libavformat/dump.c
+++ b/libavformat/dump.c
@@ -27,6 +27,7 @@
 #include "libavutil/intreadwrite.h"
 #include "libavutil/log.h"
 #include "libavutil/mastering_display_metadata.h"
+#include "libavutil/ambient_viewing_environment.h"
 #include "libavutil/dovi_meta.h"
 #include "libavutil/mathematics.h"
 #include "libavutil/opt.h"
@@ -366,6 +367,17 @@ static void dump_content_light_metadata(void *ctx, const AVPacketSideData *sd)
            metadata->MaxCLL, metadata->MaxFALL);
 }
 
+static void dump_ambient_viewing_environment_metadata(void *ctx, const AVPacketSideData *sd)
+{
+    const AVAmbientViewingEnvironment *ambient =
+        (const AVAmbientViewingEnvironment *)sd->data;
+    av_log(ctx, AV_LOG_INFO, "Ambient Viewing Environment, "
+           "ambient_illuminance=%f, ambient_light_x=%f, ambient_light_y=%f",
+           av_q2d(ambient->ambient_illuminance),
+           av_q2d(ambient->ambient_light_x),
+           av_q2d(ambient->ambient_light_y));
+}
+
 static void dump_spherical(void *ctx, const AVCodecParameters *par,
                            const AVPacketSideData *sd)
 {
@@ -497,6 +509,9 @@ static void dump_sidedata(void *ctx, const AVStream *st, const char *indent)
             av_log(ctx, AV_LOG_INFO, "SMPTE ST 12-1:2014: ");
             dump_s12m_timecode(ctx, st, sd);
             break;
+        case AV_PKT_DATA_AMBIENT_VIEWING_ENVIRONMENT:
+            dump_ambient_viewing_environment_metadata(ctx, sd);
+            break;
         default:
             av_log(ctx, AV_LOG_INFO, "unknown side data type %d "
                    "(%"SIZE_SPECIFIER" bytes)", sd->type, sd->size);
diff --git a/libavformat/isom.h b/libavformat/isom.h
index 4b1cd42f0f..e24dfb3dd0 100644
--- a/libavformat/isom.h
+++ b/libavformat/isom.h
@@ -29,6 +29,7 @@
 
 #include "libavutil/encryption_info.h"
 #include "libavutil/mastering_display_metadata.h"
+#include "libavutil/ambient_viewing_environment.h"
 #include "libavutil/spherical.h"
 #include "libavutil/stereo3d.h"
 
@@ -249,6 +250,8 @@ typedef struct MOVStreamContext {
     AVMasteringDisplayMetadata *mastering;
     AVContentLightMetadata *coll;
     size_t coll_size;
+    AVAmbientViewingEnvironment *ambient;
+    size_t ambient_size;
 
     uint32_t format;
 
diff --git a/libavformat/mov.c b/libavformat/mov.c
index 444aca5235..726341736e 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -6010,6 +6010,31 @@ static int mov_read_clli(MOVContext *c, AVIOContext *pb, MOVAtom atom)
     return 0;
 }
 
+static int mov_read_amve(MOVContext *c, AVIOContext *pb, MOVAtom atom)
+{
+    MOVStreamContext *sc;
+    const int illuminance_den = 10000;
+    const int ambient_den = 50000;
+    if (c->fc->nb_streams < 1)
+        return AVERROR_INVALIDDATA;
+    sc = c->fc->streams[c->fc->nb_streams - 1]->priv_data;
+    if (atom.size < 6) {
+        av_log(c->fc, AV_LOG_ERROR, "Empty Ambient Viewing Environment Info box\n");
+        return AVERROR_INVALIDDATA;
+    }
+    if (sc->ambient){
+        av_log(c->fc, AV_LOG_WARNING, "Ignoring duplicate AMVE\n");
+        return 0;
+    }
+    sc->ambient = av_ambient_viewing_environment_alloc(&sc->ambient_size);
+    if (!sc->ambient)
+        return AVERROR(ENOMEM);
+    sc->ambient->ambient_illuminance  = av_make_q(avio_rb32(pb), illuminance_den);
+    sc->ambient->ambient_light_x = av_make_q(avio_rb16(pb), ambient_den);
+    sc->ambient->ambient_light_y = av_make_q(avio_rb16(pb), ambient_den);
+    return 0;
+}
+
 static int mov_read_st3d(MOVContext *c, AVIOContext *pb, MOVAtom atom)
 {
     AVStream *st;
@@ -7921,6 +7946,7 @@ static const MOVParseTableEntry mov_default_parse_table[] = {
 { MKTAG('p','c','m','C'), mov_read_pcmc }, /* PCM configuration box */
 { MKTAG('p','i','t','m'), mov_read_pitm },
 { MKTAG('e','v','c','C'), mov_read_glbl },
+{ MKTAG('a','m','v','e'), mov_read_amve }, /* ambient viewing environment box */
 { 0, NULL }
 };
 
@@ -8391,6 +8417,7 @@ static int mov_read_close(AVFormatContext *s)
         av_freep(&sc->spherical);
         av_freep(&sc->mastering);
         av_freep(&sc->coll);
+        av_freep(&sc->ambient);
     }
 
     av_freep(&mov->dv_demux);
@@ -8756,6 +8783,15 @@ static int mov_read_header(AVFormatContext *s)
 
                 sc->coll = NULL;
             }
+            if (sc->ambient) {
+                err = av_stream_add_side_data(st, AV_PKT_DATA_AMBIENT_VIEWING_ENVIRONMENT,
+                                              (uint8_t *)sc->ambient,
+                                              sc->ambient_size);
+                if (err < 0)
+                    return err;
+
+                sc->ambient = NULL;
+            }
             break;
         }
     }
diff --git a/libavformat/movenc.c b/libavformat/movenc.c
index f1cc80b1b3..9c6109f4bd 100644
--- a/libavformat/movenc.c
+++ b/libavformat/movenc.c
@@ -2220,6 +2220,27 @@ static int mov_write_mdcv_tag(AVIOContext *pb, MOVTrack *track)
     return 32;
 }
 
+static int mov_write_amve_tag(AVIOContext *pb, MOVTrack *track)
+{
+    const int illuminance_den = 10000;
+    const int ambient_den = 50000;
+    const uint8_t *side_data;
+    const AVAmbientViewingEnvironment *ambient;
+
+    side_data = av_stream_get_side_data(track->st, AV_PKT_DATA_AMBIENT_VIEWING_ENVIRONMENT, NULL);
+    ambient = (const AVAmbientViewingEnvironment*)side_data;
+    if (!ambient || !ambient->ambient_illuminance.num) {
+        return 0;
+    }
+
+    avio_wb32(pb, 16); // size
+    ffio_wfourcc(pb, "amve");
+    avio_wb32(pb, rescale_mdcv(ambient->ambient_illuminance, illuminance_den));
+    avio_wb16(pb, rescale_mdcv(ambient->ambient_light_x, ambient_den));
+    avio_wb16(pb, rescale_mdcv(ambient->ambient_light_y, ambient_den));
+    return 16;
+}
+
 static void find_compressor(char * compressor_name, int len, MOVTrack *track)
 {
     AVDictionaryEntry *encoder;
@@ -2430,6 +2451,7 @@ static int mov_write_video_tag(AVFormatContext *s, AVIOContext *pb, MOVMuxContex
     if (track->mode == MODE_MOV || track->mode == MODE_MP4) {
         mov_write_clli_tag(pb, track);
         mov_write_mdcv_tag(pb, track);
+        mov_write_amve_tag(pb, track);
     }
 
     if (track->mode == MODE_MP4 && mov->fc->strict_std_compliance <= FF_COMPLIANCE_UNOFFICIAL) {
-- 
2.39.2 (Apple Git-143)



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