[FFmpeg-devel] [PATCHv4] mov: Evaluate the movie display matrix
Vittorio Giovara
vittorio.giovara at gmail.com
Fri Nov 4 00:54:53 EET 2016
This matrix needs to be applied after all others have (currently only
display matrix from trak), but cannot be handled in movie box, since
streams are not allocated yet. So store it in main context, and apply
it when appropriate, that is after parsing the tkhd one.
Signed-off-by: Vittorio Giovara <vittorio.giovara at gmail.com>
---
Updated according everybody's review. Changed the loop to always perform
multiplication, so that it's simpler to apply and to test. Changed computation
to fixed point instead of conversion to double.
Added a single test to cover this usecase, https://www.dropbox.com/s/qfio4bjhkpz3p4o/displaymatrix.mov?dl=0
Please CC.
Vittorio
libavformat/isom.h | 1 +
libavformat/mov.c | 48 +++++++++++++++++++++++++++++-----------
tests/fate/mov.mak | 5 ++++-
tests/ref/fate/mov-displaymatrix | 10 +++++++++
4 files changed, 50 insertions(+), 14 deletions(-)
create mode 100644 tests/ref/fate/mov-displaymatrix
diff --git a/libavformat/isom.h b/libavformat/isom.h
index d684502..02bfedd 100644
--- a/libavformat/isom.h
+++ b/libavformat/isom.h
@@ -240,6 +240,7 @@ typedef struct MOVContext {
uint8_t *decryption_key;
int decryption_key_len;
int enable_drefs;
+ int32_t movie_display_matrix[3][3]; ///< display matrix from mvhd
} MOVContext;
int ff_mp4_read_descr_len(AVIOContext *pb);
diff --git a/libavformat/mov.c b/libavformat/mov.c
index 35782fe..beedaef 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -1231,6 +1231,7 @@ static int mov_read_mdhd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
static int mov_read_mvhd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
+ int i;
int64_t creation_time;
int version = avio_r8(pb); /* version */
avio_rb24(pb); /* flags */
@@ -1258,7 +1259,12 @@ static int mov_read_mvhd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
avio_skip(pb, 10); /* reserved */
- avio_skip(pb, 36); /* display matrix */
+ /* movie display matrix, store it in main context and use it later on */
+ for (i = 0; i < 3; i++) {
+ c->movie_display_matrix[i][0] = avio_rb32(pb); // 16.16 fixed point
+ c->movie_display_matrix[i][1] = avio_rb32(pb); // 16.16 fixed point
+ c->movie_display_matrix[i][2] = avio_rb32(pb); // 2.30 fixed point
+ }
avio_rb32(pb); /* preview time */
avio_rb32(pb); /* preview duration */
@@ -3815,12 +3821,22 @@ static int mov_read_meta(MOVContext *c, AVIOContext *pb, MOVAtom atom)
return 0;
}
+// return 1 when matrix is identity, 0 otherwise
+#define IS_MATRIX_IDENT(matrix) \
+ ( (matrix)[0][0] == (1 << 16) && \
+ (matrix)[1][1] == (1 << 16) && \
+ (matrix)[2][2] == (1 << 30) && \
+ !(matrix)[0][1] && !(matrix)[0][2] || \
+ !(matrix)[1][0] && !(matrix)[1][2] || \
+ !(matrix)[2][0] && !(matrix)[2][1])
+
static int mov_read_tkhd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
- int i;
+ int i, j, e;
int width;
int height;
int display_matrix[3][3];
+ int res_display_matrix[3][3] = { { 0 } };
AVStream *st;
MOVStreamContext *sc;
int version;
@@ -3870,15 +3886,20 @@ static int mov_read_tkhd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
sc->width = width >> 16;
sc->height = height >> 16;
- // save the matrix and add rotate metadata when it is not the default
- // identity
- if (display_matrix[0][0] != (1 << 16) ||
- display_matrix[1][1] != (1 << 16) ||
- display_matrix[2][2] != (1 << 30) ||
- display_matrix[0][1] || display_matrix[0][2] ||
- display_matrix[1][0] || display_matrix[1][2] ||
- display_matrix[2][0] || display_matrix[2][1]) {
- int i, j;
+ // apply the moov display matrix (after the tkhd one)
+ for (i = 0; i < 3; i++) {
+ const int sh[3] = { 16, 16, 30 };
+ for (j = 0; j < 3; j++) {
+ for (e = 0; e < 3; e++) {
+ res_display_matrix[i][j] +=
+ ((int64_t) display_matrix[i][e] *
+ c->movie_display_matrix[e][j]) >> sh[e];
+ }
+ }
+ }
+
+ // save the matrix when it is not the default identity
+ if (!IS_MATRIX_IDENT(res_display_matrix)) {
double rotate;
av_freep(&sc->display_matrix);
@@ -3888,7 +3909,7 @@ static int mov_read_tkhd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
for (i = 0; i < 3; i++)
for (j = 0; j < 3; j++)
- sc->display_matrix[i * 3 + j] = display_matrix[i][j];
+ sc->display_matrix[i * 3 + j] = res_display_matrix[i][j];
rotate = av_display_rotation_get(sc->display_matrix);
if (!isnan(rotate)) {
@@ -3907,7 +3928,8 @@ static int mov_read_tkhd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
double disp_transform[2];
for (i = 0; i < 2; i++)
- disp_transform[i] = hypot(display_matrix[i][0], display_matrix[i][1]);
+ disp_transform[i] = hypot(sc->display_matrix[0 + i],
+ sc->display_matrix[3 + i]);
if (disp_transform[0] > 0 && disp_transform[1] > 0 &&
disp_transform[0] < (1<<24) && disp_transform[1] < (1<<24) &&
diff --git a/tests/fate/mov.mak b/tests/fate/mov.mak
index 6b79832..2c73d73 100644
--- a/tests/fate/mov.mak
+++ b/tests/fate/mov.mak
@@ -5,7 +5,8 @@ FATE_MOV = fate-mov-3elist \
fate-mov-elist-starts-ctts-2ndsample \
fate-mov-1elist-ends-last-bframe \
fate-mov-2elist-elist1-ends-bframe \
- fate-mov-aac-2048-priming
+ fate-mov-aac-2048-priming \
+ fate-mov-displaymatrix
FATE_SAMPLES_AVCONV += $(FATE_MOV)
@@ -30,3 +31,5 @@ fate-mov-2elist-elist1-ends-bframe: CMD = framemd5 -i $(TARGET_SAMPLES)/mov/mov-
fate-mov-aac-2048-priming: ffprobe$(PROGSSUF)$(EXESUF)
fate-mov-aac-2048-priming: CMD = run ffprobe$(PROGSSUF)$(EXESUF) -show_packets -print_format compact $(TARGET_SAMPLES)/mov/aac-2048-priming.mov
+
+fate-mov-displaymatrix: CMD = framemd5 -i $(TARGET_SAMPLES)/mov/displaymatrix.mov -frames 1
diff --git a/tests/ref/fate/mov-displaymatrix b/tests/ref/fate/mov-displaymatrix
new file mode 100644
index 0000000..52528c1
--- /dev/null
+++ b/tests/ref/fate/mov-displaymatrix
@@ -0,0 +1,10 @@
+#format: frame checksums
+#version: 2
+#hash: MD5
+#tb 0: 1001/30000
+#media_type 0: video
+#codec_id 0: rawvideo
+#dimensions 0: 240x160
+#sar 0: 2/1
+#stream#, dts, pts, duration, size, hash
+0, 0, 0, 1, 57600, be949aa661551010f461069804f68e76
--
2.10.0
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