h264_mp4toannexb: Try to avoid four byte startcodes

According to the H.264 specifications, the only NAL units that need to
have four byte startcodes in H.264 Annex B format are SPS/PPS units and
units that start a new access unit. Before af7e953a, the first of these
conditions wasn't upheld as already existing in-band parameter sets
would not automatically be written with a four byte startcode, but only
when they already were at the beginning of their input packets. But it
made four byte startcodes be used too often as every unit that is written
together with a parameter set that is inserted from extradata received a
four byte startcode although a three byte start code would suffice
unless the unit itself were a parameter set.

FATE has been updated to reflect the changes. Although the patch leaves
the extradata unchanged, the size of the extradata according to the FATE
reports changes. This is due to a quirk in ff_h2645_packet_split which
is used by extract_extradata: If the input is Annex B, the first zero of
a four byte startcode is considered a part of the last unit (if any).

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

diff --git a/libavcodec/h264_mp4toannexb_bsf.c b/libavcodec/h264_mp4toannexb_bsf.c
index 561126c997d16881ec67d1255152d79821c5ff86..9aed3f14354b71f36e6311da3bd5241aa3fda406 100644 (file)
--- a/libavcodec/h264_mp4toannexb_bsf.c
+++ b/libavcodec/h264_mp4toannexb_bsf.c
@@ -47,7 +47,7 @@ static int alloc_and_copy(AVPacket *out,
                           const uint8_t *in, uint32_t in_size, int ps)
 {
     uint32_t offset         = out->size;
-    uint8_t start_code_size = offset == 0 || ps ? 4 : 3;
+    uint8_t start_code_size = offset == 0 && sps_pps_size == 0 || ps ? 4 : 3;
     int err;
 
     err = av_grow_packet(out, sps_pps_size + in_size + start_code_size);
@@ -244,7 +244,7 @@ static int h264_mp4toannexb_filter(AVBSFContext *ctx, AVPacket *out)
         if (s->new_idr && unit_type == H264_NAL_IDR_SLICE && !s->idr_sps_seen && !s->idr_pps_seen) {
             if ((ret=alloc_and_copy(out,
                                ctx->par_out->extradata, ctx->par_out->extradata_size,
-                               buf, nal_size, 1)) < 0)
+                               buf, nal_size, 0)) < 0)
                 goto fail;
             s->new_idr = 0;
         /* if only SPS has been seen, also insert PPS */
@@ -255,7 +255,7 @@ static int h264_mp4toannexb_filter(AVBSFContext *ctx, AVPacket *out)
                     goto fail;
             } else if ((ret = alloc_and_copy(out,
                                         s->pps, s->pps_size,
-                                        buf, nal_size, 1)) < 0)
+                                        buf, nal_size, 0)) < 0)
                 goto fail;
         } else {
             if ((ret=alloc_and_copy(out, NULL, 0, buf, nal_size, unit_type == H264_NAL_SPS || unit_type == H264_NAL_PPS)) < 0)

diff --git a/tests/ref/fate/h264-bsf-mp4toannexb b/tests/ref/fate/h264-bsf-mp4toannexb
index 7cd086a268cd1e84b97957ff10c3c557f777bbdf..2049f39701e32f49d39b1908f2bb4d3f927f6c7d 100644 (file)
--- a/tests/ref/fate/h264-bsf-mp4toannexb
+++ b/tests/ref/fate/h264-bsf-mp4toannexb
@@ -1 +1 @@
-f340e7ca9a46d437af4e96f6c8de221c
+5f04c27cc6ee8625fe2405fb0f7da9a3

diff --git a/tests/ref/fate/h264_mp4toannexb_ticket2991 b/tests/ref/fate/h264_mp4toannexb_ticket2991
index 3245ef442c62eb4359b32012e66f450e76f9f4a0..76bdf3cae79c759b7cfa199a97ff6acd0a261afc 100644 (file)
--- a/tests/ref/fate/h264_mp4toannexb_ticket2991
+++ b/tests/ref/fate/h264_mp4toannexb_ticket2991
@@ -1,12 +1,12 @@
-dba672c154b41414cf26aae967c27eef *tests/data/fate/h264_mp4toannexb_ticket2991.h264
-1985823 tests/data/fate/h264_mp4toannexb_ticket2991.h264
-#extradata 0:       48, 0x47ae0d55
+05d66e60ab22ee004720e0051af0fe74 *tests/data/fate/h264_mp4toannexb_ticket2991.h264
+1985815 tests/data/fate/h264_mp4toannexb_ticket2991.h264
+#extradata 0:       47, 0x3a590d55
 #tb 0: 1/1200000
 #media_type 0: video
 #codec_id 0: h264
 #dimensions 0: 1280x720
 #sar 0: 3/4
-0,          0,          0,    48000,    37127, 0xc125184c
+0,          0,          0,    48000,    37126, 0xb020184c
 0,      48000,      48000,    40040,     6920, 0x8512361a, F=0x0
 0,      88040,      88040,    40040,     7550, 0x1bc56ed4, F=0x0
 0,     128081,     128081,    40040,     8752, 0xb8c6f0a1, F=0x0
@@ -21,7 +21,7 @@ dba672c154b41414cf26aae967c27eef *tests/data/fate/h264_mp4toannexb_ticket2991.h2
 0,     488444,     488444,    40040,    11234, 0x83cbd9fd, F=0x0
 0,     528485,     528485,    40040,    17616, 0xfdf95104, F=0x0
 0,     568525,     568525,    40040,    10689, 0x9633d32b, F=0x0
-0,     608566,     608566,    40040,    45292, 0x66dd2cf6
+0,     608566,     608566,    40040,    45291, 0x543c2cf6
 0,     648606,     648606,    40040,    20837, 0x051abfab, F=0x0
 0,     688646,     688646,    40040,    21418, 0xe2a59d70, F=0x0
 0,     728687,     728687,    40040,    15643, 0x15cf2cec, F=0x0
@@ -36,7 +36,7 @@ dba672c154b41414cf26aae967c27eef *tests/data/fate/h264_mp4toannexb_ticket2991.h2
 0,    1089050,    1089050,    40040,    13130, 0xcbb6bb8e, F=0x0
 0,    1129091,    1129091,    40040,    16180, 0x5d188a7a, F=0x0
 0,    1169131,    1169131,    40040,    14961, 0x9ff2f463, F=0x0
-0,    1209172,    1209172,    40040,    54297, 0xf98d30ed
+0,    1209172,    1209172,    40040,    54296, 0xe6ec30ed
 0,    1249212,    1249212,    40040,    11500, 0x8c4852c9, F=0x0
 0,    1289252,    1289252,    40040,    12065, 0xfb7954c3, F=0x0
 0,    1329293,    1329293,    40040,    12532, 0xf0a935d3, F=0x0
@@ -51,7 +51,7 @@ dba672c154b41414cf26aae967c27eef *tests/data/fate/h264_mp4toannexb_ticket2991.h2
 0,    1689656,    1689656,    40040,    13250, 0xfed0deb8, F=0x0
 0,    1729697,    1729697,    40040,    13360, 0xbf92d476, F=0x0
 0,    1769737,    1769737,    40040,    11749, 0x3041eaf1, F=0x0
-0,    1809778,    1809778,    40040,    23998, 0xee87d5c4
+0,    1809778,    1809778,    40040,    23997, 0xdbe6d5c4
 0,    1849818,    1849818,    40040,    16065, 0xe8f715b7, F=0x0
 0,    1889858,    1889858,    40040,    16441, 0x0a4e060f, F=0x0
 0,    1929899,    1929899,    40040,    17395, 0xa8edecc2, F=0x0
@@ -66,7 +66,7 @@ dba672c154b41414cf26aae967c27eef *tests/data/fate/h264_mp4toannexb_ticket2991.h2
 0,    2290262,    2290262,    40040,    13748, 0xed26aeb4, F=0x0
 0,    2330303,    2330303,    40040,    15092, 0x3c983538, F=0x0
 0,    2370343,    2370343,    40040,    14636, 0x9b278a6c, F=0x0
-0,    2410384,    2410384,    40040,    29135, 0x0a34be18
+0,    2410384,    2410384,    40040,    29134, 0xf784be18
 0,    2450424,    2450424,    40040,    10232, 0x5408e15b, F=0x0
 0,    2490464,    2490464,    40040,     9769, 0xc93cb7f9, F=0x0
 0,    2530505,    2530505,    40040,    14454, 0x45230dbe, F=0x0
@@ -81,7 +81,7 @@ dba672c154b41414cf26aae967c27eef *tests/data/fate/h264_mp4toannexb_ticket2991.h2
 0,    2890868,    2890868,    40040,    14801, 0x40bae016, F=0x0
 0,    2930909,    2930909,    40040,    17303, 0x9ce1fd31, F=0x0
 0,    2970949,    2970949,    40040,    17678, 0x9bd66141, F=0x0
-0,    3010990,    3010990,    40040,    48673, 0x44b6ce46
+0,    3010990,    3010990,    40040,    48672, 0x3215ce46
 0,    3051030,    3051030,    40040,    11894, 0x12e1fece, F=0x0
 0,    3091070,    3091070,    40040,    16514, 0xc57aed05, F=0x0
 0,    3131111,    3131111,    40040,    13044, 0x61914fa0, F=0x0
@@ -96,7 +96,7 @@ dba672c154b41414cf26aae967c27eef *tests/data/fate/h264_mp4toannexb_ticket2991.h2
 0,    3491474,    3491474,    40040,    12208, 0x81a587c0, F=0x0
 0,    3531515,    3531515,    40040,    14709, 0x5dffbe04, F=0x0
 0,    3571555,    3571555,    40040,    14390, 0xbfd1e041, F=0x0
-0,    3611596,    3611596,    40040,    37237, 0xfa9a24b1
+0,    3611596,    3611596,    40040,    37236, 0xe7f924b1
 0,    3651636,    3651636,    40040,    14056, 0x24714c7c, F=0x0
 0,    3691676,    3691676,    40040,    19438, 0x0c50dcd5, F=0x0
 0,    3731717,    3731717,    40040,    21728, 0x7eea4a11, F=0x0
@@ -111,7 +111,7 @@ dba672c154b41414cf26aae967c27eef *tests/data/fate/h264_mp4toannexb_ticket2991.h2
 0,    4092080,    4092080,    40040,    16878, 0x98efbae2, F=0x0
 0,    4132121,    4132121,    40040,    14685, 0x1bf78d65, F=0x0
 0,    4172161,    4172161,    40040,    13127, 0x0b91881d, F=0x0
-0,    4212202,    4212202,    40040,    29391, 0x0955ed6b
+0,    4212202,    4212202,    40040,    29390, 0xf6a5ed6b
 0,    4252242,    4252242,    40040,    12576, 0xe9845ded, F=0x0
 0,    4292282,    4292282,    40040,    12599, 0x96a79ab8, F=0x0
 0,    4332323,    4332323,    40040,    16134, 0xb4c36d3f, F=0x0

diff --git a/tests/ref/fate/h264_mp4toannexb_ticket5927 b/tests/ref/fate/h264_mp4toannexb_ticket5927
index 006ea398fd6e0481e37b41984f79760aab41a503..95e35c4d802f2a1b258cf0e69672e0f169de2960 100644 (file)
--- a/tests/ref/fate/h264_mp4toannexb_ticket5927
+++ b/tests/ref/fate/h264_mp4toannexb_ticket5927
@@ -1,12 +1,12 @@
-562487bfea635cdadbc23d390322b589 *tests/data/fate/h264_mp4toannexb_ticket5927.h264
-595585 tests/data/fate/h264_mp4toannexb_ticket5927.h264
-#extradata 0:       34, 0x8df608f8
+a3b02fd09392e01619cebc959d4d9ff2 *tests/data/fate/h264_mp4toannexb_ticket5927.h264
+595583 tests/data/fate/h264_mp4toannexb_ticket5927.h264
+#extradata 0:       33, 0x84fe08f8
 #tb 0: 1/1200000
 #media_type 0: video
 #codec_id 0: h264
 #dimensions 0: 1920x1080
 #sar 0: 0/1
-0,     -48000, -9223372036854775808,    48000,   247994, 0x2e1e21ea
+0,     -48000, -9223372036854775808,    48000,   247993, 0x1ce821ea
 0,          0, -9223372036854775808,    48000,    43354, 0xa05dca6f, F=0x0
 0,      48000, -9223372036854775808,    48000,    11423, 0x5e8086dd, F=0x0
 0,      96000, -9223372036854775808,    48000,    50798, 0x145fbe4f, F=0x0
@@ -18,4 +18,4 @@
 0,     384000, -9223372036854775808,    48000,    54483, 0xefead99f, F=0x0
 0,     432000, -9223372036854775808,    48000,    13705, 0x23cd27e8, F=0x0
 0,     480000, -9223372036854775808,    48000,    22308, 0x4093b5af, F=0x0
-0,     528000, -9223372036854775808,    48000,     6370, 0x96c12aa1
+0,     528000, -9223372036854775808,    48000,     6369, 0x858b2aa1

diff --git a/tests/ref/fate/h264_mp4toannexb_ticket5927_2 b/tests/ref/fate/h264_mp4toannexb_ticket5927_2
index 51432b153533f4a75b562dcad63fe6a980c50c45..8db6a7e54a7d726a3adfaa49d2c2b469a4d8d306 100644 (file)
--- a/tests/ref/fate/h264_mp4toannexb_ticket5927_2
+++ b/tests/ref/fate/h264_mp4toannexb_ticket5927_2
@@ -1,12 +1,12 @@
-562487bfea635cdadbc23d390322b589 *tests/data/fate/h264_mp4toannexb_ticket5927_2.h264
-595585 tests/data/fate/h264_mp4toannexb_ticket5927_2.h264
-#extradata 0:       34, 0x8df608f8
+a3b02fd09392e01619cebc959d4d9ff2 *tests/data/fate/h264_mp4toannexb_ticket5927_2.h264
+595583 tests/data/fate/h264_mp4toannexb_ticket5927_2.h264
+#extradata 0:       33, 0x84fe08f8
 #tb 0: 1/1200000
 #media_type 0: video
 #codec_id 0: h264
 #dimensions 0: 1920x1080
 #sar 0: 0/1
-0,     -48000, -9223372036854775808,    48000,   247994, 0x2e1e21ea
+0,     -48000, -9223372036854775808,    48000,   247993, 0x1ce821ea
 0,          0, -9223372036854775808,    48000,    43354, 0xa05dca6f, F=0x0
 0,      48000, -9223372036854775808,    48000,    11423, 0x5e8086dd, F=0x0
 0,      96000, -9223372036854775808,    48000,    50798, 0x145fbe4f, F=0x0
@@ -18,4 +18,4 @@
 0,     384000, -9223372036854775808,    48000,    54483, 0xefead99f, F=0x0
 0,     432000, -9223372036854775808,    48000,    13705, 0x23cd27e8, F=0x0
 0,     480000, -9223372036854775808,    48000,    22308, 0x4093b5af, F=0x0
-0,     528000, -9223372036854775808,    48000,     6370, 0x96c12aa1
+0,     528000, -9223372036854775808,    48000,     6369, 0x858b2aa1

diff --git a/tests/ref/fate/segment-mp4-to-ts b/tests/ref/fate/segment-mp4-to-ts
index b5accb60f72683f3a0af8c9e94ae7ab40a00cedb..847c1a297db902e3b0a069165b83fe0bc98b9c94 100644 (file)
--- a/tests/ref/fate/segment-mp4-to-ts
+++ b/tests/ref/fate/segment-mp4-to-ts
@@ -1,10 +1,10 @@
-#extradata 0:       51, 0x5d140df9
+#extradata 0:       50, 0x4f1b0df9
 #tb 0: 1/90000
 #media_type 0: video
 #codec_id 0: h264
 #dimensions 0: 640x360
 #sar 0: 1/1
-0,      -7200,          0,        0,    22631, 0x9cec9541, S=1,        1, 0x00e000e0
+0,      -7200,          0,        0,    22630, 0x9b109541, S=1,        1, 0x00e000e0
 0,      -3600,      14400,        0,     4021, 0xbf7cdb02, F=0x0, S=1,        1, 0x00e000e0
 0,          0,       7200,        0,     1096, 0x4f162690, F=0x0, S=1,        1, 0x00e000e0
 0,       3600,       3600,        0,      687, 0x00394b95, F=0x0, S=1,        1, 0x00e000e0