[FFmpeg-devel] [PATCH v3 4/5] avformat/mov: Add support for exporting Video Extension Usage info

Derek Buitenhuis derek.buitenhuis at gmail.com
Mon Jun 17 16:44:22 EEST 2024


This box is provided by files created by the Apple Vision Pro, as well
as the iPhone 15+ when capture for Vision Pro is enabled.

The boxes are a mix of things documented by Apple in some PDFs, their
API docs, and reverse engineering. Ideally we will have a real spec
one day.

Links:
  * https://developer.apple.com/av-foundation/Stereo-Video-ISOBMFF-Extensions.pdf
  * https://developer.apple.com/documentation/videotoolbox/kvtcompressionpropertykey_horizontaldisparityadjustment
  * https://developer.apple.com/documentation/videotoolbox/kvtcompressionpropertykey_stereocamerabaseline
  * https://developer.apple.com/documentation/videotoolbox/kvtcompressionpropertykey_heroeye

Signed-off-by: Derek Buitenhuis <derek.buitenhuis at gmail.com>
---
Only difference from v2 is s/RECTANGULAR/RECTILINEAR/.
---
 libavformat/mov.c | 279 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 279 insertions(+)

diff --git a/libavformat/mov.c b/libavformat/mov.c
index 9016cd5ad0..0f8d7e83b2 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -6477,6 +6477,284 @@ static int mov_read_sv3d(MOVContext *c, AVIOContext *pb, MOVAtom atom)
     return 0;
 }
 
+static int mov_read_vexu_proj(MOVContext *c, AVIOContext *pb, MOVAtom atom)
+{
+    AVStream *st;
+    MOVStreamContext *sc;
+    int size;
+    uint32_t tag;
+    enum AVSphericalProjection projection;
+
+    if (c->fc->nb_streams < 1)
+        return 0;
+
+    st = c->fc->streams[c->fc->nb_streams - 1];
+    sc = st->priv_data;
+
+    if (atom.size != 16) {
+        av_log(c->fc, AV_LOG_ERROR, "Invalid size for proj box: %"PRIu64"\n", atom.size);
+        return AVERROR_INVALIDDATA;
+    }
+
+    size = avio_rb32(pb);
+    if (size != 16) {
+        av_log(c->fc, AV_LOG_ERROR, "Invalid size for prji box: %d\n", size);
+        return AVERROR_INVALIDDATA;
+    }
+
+    tag = avio_rl32(pb);
+    if (tag != MKTAG('p','r','j','i')) {
+        av_log(c->fc, AV_LOG_ERROR, "Invalid child box of proj box: 0x%08X\n", tag);
+        return AVERROR_INVALIDDATA;
+    }
+
+    avio_skip(pb, 1); // version
+    avio_skip(pb, 3); // flags
+
+    tag = avio_rl32(pb);
+    switch (tag) {
+    case MKTAG('r','e','c','t'):
+        projection = AV_SPHERICAL_RECTILINEAR;
+        break;
+    case MKTAG('e','q','u','i'):
+        projection = AV_SPHERICAL_EQUIRECTANGULAR;
+        break;
+    case MKTAG('h','e','q','u'):
+        projection = AV_SPHERICAL_HALF_EQUIRECTANGULAR;
+        break;
+    case MKTAG('f','i','s','h'):
+        projection = AV_SPHERICAL_FISHEYE;
+        break;
+    default:
+        av_log(c->fc, AV_LOG_ERROR, "Invalid projection type in prji box: 0x%08X\n", tag);
+        return AVERROR_INVALIDDATA;
+    }
+
+    sc->spherical = av_spherical_alloc(&sc->spherical_size);
+    if (!sc->spherical)
+        return AVERROR(ENOMEM);
+
+    sc->spherical->projection = projection;
+
+    return 0;
+}
+
+static int mov_read_eyes(MOVContext *c, AVIOContext *pb, MOVAtom atom)
+{
+    AVStream *st;
+    MOVStreamContext *sc;
+    int size, flags = 0;
+    int64_t remaining;
+    uint32_t tag, baseline = 0;
+    enum AVStereo3DView view = AV_STEREO3D_VIEW_PACKED;
+    enum AVStereo3DPrimaryEye primary_eye = AV_PRIMARY_EYE_NONE;
+    int32_t horizontal_disparity_adjustment = 0;
+
+    if (c->fc->nb_streams < 1)
+        return 0;
+
+    st = c->fc->streams[c->fc->nb_streams - 1];
+    sc = st->priv_data;
+
+    remaining = atom.size;
+    while (remaining > 0) {
+        size = avio_rb32(pb);
+        if (size < 8 || size > remaining ) {
+            av_log(c->fc, AV_LOG_ERROR, "Invalid child size in eyes box\n");
+            return AVERROR_INVALIDDATA;
+        }
+
+        tag = avio_rl32(pb);
+        switch (tag) {
+        case MKTAG('s','t','r','i'): {
+            int has_right, has_left;
+            uint8_t tmp;
+            if (size != 13) {
+                av_log(c->fc, AV_LOG_ERROR, "Invalid size of stri box: %d\n", size);
+                return AVERROR_INVALIDDATA;
+            }
+            avio_skip(pb, 1); // version
+            avio_skip(pb, 3); // flags
+
+            tmp = avio_r8(pb);
+
+            // eye_views_reversed
+            if (tmp & 8) {
+                flags |= AV_STEREO3D_FLAG_INVERT;
+            }
+            // has_additional_views
+            if (tmp & 4) {
+                // skip...
+            }
+
+            has_right = tmp & 2; // has_right_eye_view
+            has_left = tmp & 1; // has_left_eye_view
+
+            if (has_left && has_right)
+                view = AV_STEREO3D_VIEW_PACKED;
+            else if (has_left)
+                view = AV_STEREO3D_VIEW_LEFT;
+            else if (has_right)
+                view = AV_STEREO3D_VIEW_RIGHT;
+            break;
+        }
+        case MKTAG('h','e','r','o'): {
+            int tmp;
+            if (size != 13) {
+                av_log(c->fc, AV_LOG_ERROR, "Invalid size of hero box: %d\n", size);
+                return AVERROR_INVALIDDATA;
+            }
+            avio_skip(pb, 1); // version
+            avio_skip(pb, 3); // flags
+
+            tmp = avio_r8(pb);
+            if (tmp == 0)
+                primary_eye = AV_PRIMARY_EYE_NONE;
+            else if (tmp == 1)
+                primary_eye = AV_PRIMARY_EYE_LEFT;
+            else if (tmp == 2)
+                primary_eye = AV_PRIMARY_EYE_RIGHT;
+            else
+                av_log(c->fc, AV_LOG_WARNING, "Unknown hero eye type: %d\n", tmp);
+
+            break;
+        }
+        case MKTAG('c','a','m','s'): {
+            uint32_t subtag;
+            int subsize;
+            if (size != 24) {
+                av_log(c->fc, AV_LOG_ERROR, "Invalid size of cams box: %d\n", size);
+                return AVERROR_INVALIDDATA;
+            }
+
+            subsize = avio_rb32(pb);
+            if (subsize != 16) {
+                av_log(c->fc, AV_LOG_ERROR, "Invalid size of blin box: %d\n", size);
+                return AVERROR_INVALIDDATA;
+            }
+
+            subtag = avio_rl32(pb);
+            if (subtag != MKTAG('b','l','i','n')) {
+                av_log(c->fc, AV_LOG_ERROR, "Expected blin box, got 0x%08X\n", subtag);
+                return AVERROR_INVALIDDATA;
+            }
+
+            avio_skip(pb, 1); // version
+            avio_skip(pb, 3); // flags
+
+            baseline = avio_rb32(pb);
+
+            break;
+        }
+        case MKTAG('c','m','f','y'): {
+            uint32_t subtag;
+            int subsize;
+            if (size != 24) {
+                av_log(c->fc, AV_LOG_ERROR, "Invalid size of cmfy box: %d\n", size);
+                return AVERROR_INVALIDDATA;
+            }
+
+            subsize = avio_rb32(pb);
+            if (subsize != 16) {
+                av_log(c->fc, AV_LOG_ERROR, "Invalid size of dadj box: %d\n", size);
+                return AVERROR_INVALIDDATA;
+            }
+
+            subtag = avio_rl32(pb);
+            if (subtag != MKTAG('d','a','d','j')) {
+                av_log(c->fc, AV_LOG_ERROR, "Expected dadj box, got 0x%08X\n", subtag);
+                return AVERROR_INVALIDDATA;
+            }
+
+            avio_skip(pb, 1); // version
+            avio_skip(pb, 3); // flags
+
+            horizontal_disparity_adjustment = (int32_t) avio_rb32(pb);
+
+            break;
+        }
+        default:
+            av_log(c->fc, AV_LOG_WARNING, "Unknown tag in eyes: 0x%08X\n", tag);
+            avio_skip(pb, size - 8);
+            break;
+        }
+        remaining -= size;
+    }
+
+    if (remaining != 0) {
+        av_log(c->fc, AV_LOG_ERROR, "Broken eyes box\n");
+        return AVERROR_INVALIDDATA;
+    }
+
+    if (!sc->stereo3d) {
+        sc->stereo3d = av_stereo3d_alloc();
+        if (!sc->stereo3d)
+            return AVERROR(ENOMEM);
+    }
+
+    sc->stereo3d->flags                           = flags;
+    sc->stereo3d->view                            = view;
+    sc->stereo3d->primary_eye                     = primary_eye;
+    sc->stereo3d->baseline                        = baseline;
+    sc->stereo3d->horizontal_disparity_adjustment = horizontal_disparity_adjustment;
+
+    return 0;
+}
+
+static int mov_read_vexu(MOVContext *c, AVIOContext *pb, MOVAtom atom)
+{
+    int size;
+    int64_t remaining;
+    uint32_t tag;
+
+    if (c->fc->nb_streams < 1)
+        return 0;
+
+    if (atom.size < 8) {
+        av_log(c->fc, AV_LOG_ERROR, "Empty video extension usage box\n");
+        return AVERROR_INVALIDDATA;
+    }
+
+    remaining = atom.size;
+    while (remaining > 0) {
+        size = avio_rb32(pb);
+        if (size < 8 || size > remaining ) {
+            av_log(c->fc, AV_LOG_ERROR, "Invalid child size in vexu box\n");
+            return AVERROR_INVALIDDATA;
+        }
+
+        tag = avio_rl32(pb);
+        switch (tag) {
+        case MKTAG('p','r','o','j'): {
+            MOVAtom proj = { tag, size - 8 };
+            int ret = mov_read_vexu_proj(c, pb, proj);
+            if (ret < 0)
+                return ret;
+            break;
+        }
+        case MKTAG('e','y','e','s'): {
+            MOVAtom eyes = { tag, size - 8 };
+            int ret = mov_read_eyes(c, pb, eyes);
+            if (ret < 0)
+                return ret;
+            break;
+        }
+        default:
+            av_log(c->fc, AV_LOG_WARNING, "Unknown tag in vexu: 0x%08X\n", tag);
+            avio_skip(pb, size - 8);
+            break;
+        }
+        remaining -= size;
+    }
+
+    if (remaining != 0) {
+        av_log(c->fc, AV_LOG_ERROR, "Broken vexu box\n");
+        return AVERROR_INVALIDDATA;
+    }
+
+    return 0;
+}
+
 static int mov_parse_uuid_spherical(MOVStreamContext *sc, AVIOContext *pb, size_t len)
 {
     int ret = 0;
@@ -8595,6 +8873,7 @@ static const MOVParseTableEntry mov_default_parse_table[] = {
 { MKTAG('d','f','L','a'), mov_read_dfla },
 { MKTAG('s','t','3','d'), mov_read_st3d }, /* stereoscopic 3D video box */
 { MKTAG('s','v','3','d'), mov_read_sv3d }, /* spherical video box */
+{ MKTAG('v','e','x','u'), mov_read_vexu }, /* video extension usage */
 { MKTAG('d','O','p','s'), mov_read_dops },
 { MKTAG('d','m','l','p'), mov_read_dmlp },
 { MKTAG('S','m','D','m'), mov_read_smdm },
-- 
2.43.0



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