rtpenc_h263_rfc2190: avoid misleading error output

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/rtpenc_h263_rfc2190.c

@@ -150,9 +150,12 @@ void ff_rtp_send_h263_rfc2190(AVFormatContext *s1, const uint8_t *buf, int size,
                 }
                 if (mb_info_pos < mb_info_count) {
                     const uint8_t *ptr = &mb_info[12*mb_info_pos];
+                    /* get position in bits in the input packet at which the next info block should be used */
                     uint32_t bit_pos = AV_RL32(ptr);
-                    uint32_t pos = (bit_pos + 7)/8;
-                    if (pos <= end - buf_base) {
+                    /* get position in bytes */
+                    uint32_t pos_next_mb_info = (bit_pos + 7)/8;
+                    /* check if data from the next MB info block should be used */
+                    if (pos_next_mb_info <= end - buf_base) {
                         state.quant = ptr[4];
                         state.gobn  = ptr[5];
                         state.mba   = AV_RL16(&ptr[6]);
@@ -160,13 +163,9 @@ void ff_rtp_send_h263_rfc2190(AVFormatContext *s1, const uint8_t *buf, int size,
                         state.vmv1  = (int8_t) ptr[9];
                         state.hmv2  = (int8_t) ptr[10];
                         state.vmv2  = (int8_t) ptr[11];
-                        ebits = 8 * pos - bit_pos;
-                        len   = pos - (buf - buf_base);
+                        ebits = 8 * pos_next_mb_info - bit_pos;
+                        len   = pos_next_mb_info - (buf - buf_base);
                         mb_info_pos++;
-                    } else {
-                        av_log(s1, AV_LOG_ERROR,
-                               "Unable to split H263 packet, use -mb_info %d "
-                               "or lower.\n", s->max_payload_size - 8);
                     }
                 } else {
                     av_log(s1, AV_LOG_ERROR, "Unable to split H263 packet, "