Instead of handling the problem inside NAL decoding code, add a higher
level wrapper function. This should be more robust against future
changes (and easier to read).
---
libavcodec/h264.c | 49 +++++++++++++++++++++++++++++++++++++++----------
1 file changed, 39 insertions(+), 10 deletions(-)
diff --git a/libavcodec/h264.c b/libavcodec/h264.c
index 0b5b6c2..613c633 100644
--- a/libavcodec/h264.c
+++ b/libavcodec/h264.c
@@ -32,6 +32,7 @@
#include "libavutil/stereo3d.h"
#include "libavutil/timer.h"
#include "internal.h"
+#include "bytestream.h"
#include "cabac.h"
#include "cabac_functions.h"
#include "error_resilience.h"
@@ -501,6 +502,40 @@ fail:
static int decode_nal_units(H264Context *h, const uint8_t *buf, int buf_size,
int parse_extradata);
+/* There are (invalid) samples in the wild with mp4-style extradata, where the
+ * parameter sets are stored unescaped (i.e. as RBSP).
+ * This function catches the parameter set decoding failure and tries again
+ * after escaping it */
+static int decode_extradata_ps_mp4(H264Context *h, const uint8_t *buf, int
buf_size)
+{
+ int ret;
+
+ ret = decode_nal_units(h, buf, buf_size, 1);
+ if (ret < 0) {
+ GetByteContext gbc;
+ PutByteContext pbc;
+ uint8_t escaped_buf[256];
+
+ bytestream2_init(&gbc, buf, buf_size);
+ bytestream2_init_writer(&pbc, escaped_buf, sizeof(escaped_buf));
+
+ while (bytestream2_get_bytes_left(&gbc)) {
+ uint32_t b = bytestream2_peek_be24(&gbc);
+ if (b <= 3) {
+ bytestream2_put_be24(&pbc, 3);
+ bytestream2_skip(&gbc, 2);
+ } else
+ bytestream2_put_byte(&pbc, bytestream2_get_byte(&gbc));
+ }
+
+ ret = decode_nal_units(h, escaped_buf, bytestream2_tell_p(&pbc), 1);
+ if (ret < 0)
+ return ret;
+ }
+
+ return 0;
+}
+
int ff_h264_decode_extradata(H264Context *h)
{
AVCodecContext *avctx = h->avctx;
@@ -527,7 +562,7 @@ int ff_h264_decode_extradata(H264Context *h)
nalsize = AV_RB16(p) + 2;
if (p - avctx->extradata + nalsize > avctx->extradata_size)
return AVERROR_INVALIDDATA;
- ret = decode_nal_units(h, p, nalsize, 1);
+ ret = decode_extradata_ps_mp4(h, p, nalsize);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR,
"Decoding sps %d from avcC failed\n", i);
@@ -541,7 +576,7 @@ int ff_h264_decode_extradata(H264Context *h)
nalsize = AV_RB16(p) + 2;
if (p - avctx->extradata + nalsize > avctx->extradata_size)
return AVERROR_INVALIDDATA;
- ret = decode_nal_units(h, p, nalsize, 1);
+ ret = decode_extradata_ps_mp4(h, p, nalsize);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR,
"Decoding pps %d from avcC failed\n", i);
@@ -1535,14 +1570,8 @@ again:
case NAL_SPS:
init_get_bits(&h->gb, ptr, bit_length);
ret = ff_h264_decode_seq_parameter_set(h);
- if (ret < 0 && h->is_avc && (nalsize != consumed) && nalsize) {
- av_log(h->avctx, AV_LOG_DEBUG,
- "SPS decoding failure, trying again with the
complete NAL\n");
- init_get_bits(&h->gb, buf + buf_index + 1 - consumed,
- 8 * (nalsize - 1));
- ff_h264_decode_seq_parameter_set(h);
- }
-
+ if (ret < 0 && (h->avctx->err_recognition & AV_EF_EXPLODE))
+ goto end;
break;
case NAL_PPS:
init_get_bits(&h->gb, ptr, bit_length);
--
2.0.0
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