This allows the AC-3 decoder to be used directly with RealMedia
decoders that unlike the libavformat one do not byte-swap automatically.
Since the new code is only used in case we would fail directly otherwise
there should be no risk for regressions.
/* copy input buffer to decoder context to avoid reading past the end
of the buffer, which can be caused by a damaged input stream. */
+ if (buf_size >= 2 && AV_RB16(buf) == 0x770B) {
+ // seems to be byte-swapped AC-3
+ int cnt = FFMIN(buf_size, AC3_FRAME_BUFFER_SIZE) >> 1;
+ s->dsp.bswap16_buf((uint16_t *)s->input_buffer, (const uint16_t *)buf, cnt);
+ } else
memcpy(s->input_buffer, buf, FFMIN(buf_size, AC3_FRAME_BUFFER_SIZE));
buf = s->input_buffer;
/* initialize the GetBitContext with the start of valid AC-3 Frame */