[FFmpeg-devel] [PATCH 12/17] avformat/evcdec: deduplicate nalu length and type parsing functions

[James Almer]

Signed-off-by: James Almer <jamrial at gmail.com>
---
 libavformat/evcdec.c | 46 ++++----------------------------------------
 1 file changed, 4 insertions(+), 42 deletions(-)

diff --git a/libavformat/evcdec.c b/libavformat/evcdec.c
index 807406885a..0f17edd371 100644
--- a/libavformat/evcdec.c
+++ b/libavformat/evcdec.c
@@ -20,10 +20,9 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include "libavcodec/get_bits.h"
-#include "libavcodec/golomb.h"
 #include "libavcodec/internal.h"
 #include "libavcodec/evc.h"
+#include "libavcodec/evc_parse.h"
 #include "libavcodec/bsf.h"
 
 #include "libavutil/opt.h"
@@ -66,43 +65,6 @@ static const AVClass evc_demuxer_class = {
     .version    = LIBAVUTIL_VERSION_INT,
 };
 
-static int get_nalu_type(const uint8_t *bits, int bits_size)
-{
-    int unit_type_plus1 = 0;
-
-    if (bits_size >= EVC_NALU_HEADER_SIZE) {
-        unsigned char *p = (unsigned char *)bits;
-        // forbidden_zero_bit
-        if ((p[0] & 0x80) != 0)   // Cannot get bitstream information. Malformed bitstream.
-            return -1;
-
-        // nal_unit_type
-        unit_type_plus1 = (p[0] >> 1) & 0x3F;
-    }
-
-    return unit_type_plus1 - 1;
-}
-
-static uint32_t read_nal_unit_length(const uint8_t *bits, int bits_size)
-{
-    uint32_t nalu_len = 0;
-
-    if (bits_size >= EVC_NALU_LENGTH_PREFIX_SIZE) {
-
-        int t = 0;
-        unsigned char *p = (unsigned char *)bits;
-
-        for (int i = 0; i < EVC_NALU_LENGTH_PREFIX_SIZE; i++)
-            t = (t << 8) | p[i];
-
-        nalu_len = t;
-        if (nalu_len == 0)   // Invalid bitstream size
-            return 0;
-    }
-
-    return nalu_len;
-}
-
 static int parse_nal_units(const AVProbeData *p, EVCParserContext *ev)
 {
     int nalu_type;
@@ -112,7 +74,7 @@ static int parse_nal_units(const AVProbeData *p, EVCParserContext *ev)
 
     while (bytes_to_read > EVC_NALU_LENGTH_PREFIX_SIZE) {
 
-        nalu_size = read_nal_unit_length(bits, EVC_NALU_LENGTH_PREFIX_SIZE);
+        nalu_size = evc_read_nal_unit_length(bits, EVC_NALU_LENGTH_PREFIX_SIZE, NULL);
         if (nalu_size == 0) break;
 
         bits += EVC_NALU_LENGTH_PREFIX_SIZE;
@@ -120,7 +82,7 @@ static int parse_nal_units(const AVProbeData *p, EVCParserContext *ev)
 
         if(bytes_to_read < nalu_size) break;
 
-        nalu_type = get_nalu_type(bits, bytes_to_read);
+        nalu_type = evc_get_nalu_type(bits, bytes_to_read, NULL);
 
         if (nalu_type == EVC_SPS_NUT)
             ev->got_sps++;
@@ -218,7 +180,7 @@ static int evc_read_packet(AVFormatContext *s, AVPacket *pkt)
             return ret;
         }
 
-        nalu_size = read_nal_unit_length((const uint8_t *)&buf, EVC_NALU_LENGTH_PREFIX_SIZE);
+        nalu_size = evc_read_nal_unit_length((const uint8_t *)&buf, EVC_NALU_LENGTH_PREFIX_SIZE, s);
         if(nalu_size <= 0) {
             av_packet_unref(pkt);
             return -1;
-- 
2.41.0