This slightly changes what is considered valid in the following cases: cavsdec.c: 0x000000XX is now considered invalid. mpeg12dec.c: 0x000000XX is now considered invalid. (where X is any value)
IS_MARKER is equivalent since VC1_CODE_RES0 = 0x00000100 --- libavcodec/cavsdec.c | 2 +- libavcodec/cbs_mpeg2.c | 6 +++--- libavcodec/extract_extradata_bsf.c | 2 +- libavcodec/mpeg12.c | 2 +- libavcodec/mpeg12dec.c | 2 +- libavcodec/mpegvideo_parser.c | 2 +- libavcodec/remove_extradata_bsf.c | 8 +++----- libavcodec/startcode.h | 17 +++++++++++++++++ libavcodec/vaapi_vc1.c | 2 +- libavcodec/vc1_common.h | 4 +--- libavcodec/vc1dec.c | 2 +- libavformat/avs2dec.c | 4 ++-- libavformat/avs3dec.c | 4 ++-- libavformat/cavsvideodec.c | 2 +- libavformat/mpegvideodec.c | 2 +- libavformat/rtpenc_mpv.c | 2 +- 16 files changed, 38 insertions(+), 25 deletions(-) diff --git a/libavcodec/cavsdec.c b/libavcodec/cavsdec.c index 3e8be65968..0c19d0e3f6 100644 --- a/libavcodec/cavsdec.c +++ b/libavcodec/cavsdec.c @@ -1257,7 +1257,7 @@ static int cavs_decode_frame(AVCodecContext *avctx, AVFrame *rframe, buf_end = buf + buf_size; for(;;) { buf_ptr = avpriv_find_start_code(buf_ptr, buf_end, &stc); - if ((stc & 0xFFFFFE00) || buf_ptr == buf_end) { + if (!start_code_is_valid(stc) || buf_ptr == buf_end) { if (!h->stc) av_log(h->avctx, AV_LOG_WARNING, "no frame decoded\n"); return FFMAX(0, buf_ptr - buf); diff --git a/libavcodec/cbs_mpeg2.c b/libavcodec/cbs_mpeg2.c index 04b0c7f87d..23839ca47b 100644 --- a/libavcodec/cbs_mpeg2.c +++ b/libavcodec/cbs_mpeg2.c @@ -150,7 +150,7 @@ static int cbs_mpeg2_split_fragment(CodedBitstreamContext *ctx, start = avpriv_find_start_code(frag->data, frag->data + frag->data_size, &start_code); - if (start_code >> 8 != 0x000001) { + if (!start_code_is_valid(start_code)) { // No start code found. return AVERROR_INVALIDDATA; } @@ -172,7 +172,7 @@ static int cbs_mpeg2_split_fragment(CodedBitstreamContext *ctx, // (may be the last byte of fragment->data); end points to the byte // following the byte containing the start code identifier (or to // the end of fragment->data). - if (start_code >> 8 == 0x000001) { + if (start_code_is_valid(start_code)) { // Unit runs from start to the beginning of the start code // pointed to by end (including any padding zeroes). unit_size = (end - 4) - start; @@ -189,7 +189,7 @@ static int cbs_mpeg2_split_fragment(CodedBitstreamContext *ctx, start = end; // Do we have a further unit to add to the fragment? - } while ((start_code >> 8) == 0x000001); + } while (start_code_is_valid(start_code)); return 0; } diff --git a/libavcodec/extract_extradata_bsf.c b/libavcodec/extract_extradata_bsf.c index 329b1a6174..e698a2632e 100644 --- a/libavcodec/extract_extradata_bsf.c +++ b/libavcodec/extract_extradata_bsf.c @@ -239,7 +239,7 @@ static int extract_extradata_vc1(AVBSFContext *ctx, AVPacket *pkt, ptr = avpriv_find_start_code(ptr, end, &state); if (state == VC1_CODE_SEQHDR || state == VC1_CODE_ENTRYPOINT) { has_extradata = 1; - } else if (has_extradata && IS_MARKER(state)) { + } else if (has_extradata && start_code_is_valid(state)) { extradata_size = ptr - 4 - pkt->data; break; } diff --git a/libavcodec/mpeg12.c b/libavcodec/mpeg12.c index d78e25a777..5ff1830496 100644 --- a/libavcodec/mpeg12.c +++ b/libavcodec/mpeg12.c @@ -214,7 +214,7 @@ int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size, pc->frame_start_found = 0; if (pc->frame_start_found < 4 && state == EXT_START_CODE) pc->frame_start_found++; - if (pc->frame_start_found == 4 && (state & 0xFFFFFF00) == 0x100) { + if (pc->frame_start_found == 4 && start_code_is_valid(state)) { if (state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE) { pc->frame_start_found = 0; pc->state = -1; diff --git a/libavcodec/mpeg12dec.c b/libavcodec/mpeg12dec.c index 7133696f3c..b857353ab8 100644 --- a/libavcodec/mpeg12dec.c +++ b/libavcodec/mpeg12dec.c @@ -2446,7 +2446,7 @@ static int decode_chunks(AVCodecContext *avctx, AVFrame *picture, /* find next start code */ uint32_t start_code = -1; buf_ptr = avpriv_find_start_code(buf_ptr, buf_end, &start_code); - if (start_code > 0x1ff) { + if (!start_code_is_valid(start_code)) { if (!skip_frame) { if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) && diff --git a/libavcodec/mpegvideo_parser.c b/libavcodec/mpegvideo_parser.c index ac6efb6909..f5afa95981 100644 --- a/libavcodec/mpegvideo_parser.c +++ b/libavcodec/mpegvideo_parser.c @@ -83,7 +83,7 @@ static int mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, pc->frame_start_found = 0; if (pc->frame_start_found < 4 && state == EXT_START_CODE) pc->frame_start_found++; - if (pc->frame_start_found == 4 && (state & 0xFFFFFF00) == 0x100) { + if (pc->frame_start_found == 4 && start_code_is_valid(state)) { if (state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE) { pc->frame_start_found = 0; pc->state = -1; diff --git a/libavcodec/remove_extradata_bsf.c b/libavcodec/remove_extradata_bsf.c index 66b7d00bd8..1914cf19d5 100644 --- a/libavcodec/remove_extradata_bsf.c +++ b/libavcodec/remove_extradata_bsf.c @@ -35,8 +35,6 @@ enum RemoveFreq { REMOVE_FREQ_NONKEYFRAME, }; -#define START_CODE 0x000001 - typedef struct RemoveExtradataContext { const AVClass *class; int freq; @@ -73,7 +71,7 @@ static int h264_split(const uint8_t *buf, int buf_size) while (ptr < end) { ptr = avpriv_find_start_code(ptr, end, &state); - if ((state & 0xFFFFFF00) != 0x100) + if (!start_code_is_valid(state)) break; nalu_type = state & 0x1F; if (nalu_type == H264_NAL_SPS) { @@ -111,7 +109,7 @@ static int hevc_split(const uint8_t *buf, int buf_size) while (ptr < end) { ptr = avpriv_find_start_code(ptr, end, &state); - if ((state >> 8) != START_CODE) + if (!start_code_is_valid(state)) break; nut = (state >> 1) & 0x3F; if (nut == HEVC_NAL_VPS) @@ -171,7 +169,7 @@ static int vc1_split(const uint8_t *buf, int buf_size) ptr = avpriv_find_start_code(ptr, end, &state); if (state == VC1_CODE_SEQHDR || state == VC1_CODE_ENTRYPOINT) { charged = 1; - } else if (charged && IS_MARKER(state)) + } else if (charged && start_code_is_valid(state)) return ptr - 4 - buf; } diff --git a/libavcodec/startcode.h b/libavcodec/startcode.h index 8b75832aaf..833754af09 100644 --- a/libavcodec/startcode.h +++ b/libavcodec/startcode.h @@ -27,6 +27,23 @@ #include <stdint.h> +#include "libavutil/attributes.h" + +/** + * @brief Test whether a start code found by avpriv_find_start_code() is valid. + * + * Use this to test the validity of a start code especially if a start code can + * be at the end of the buffer, where testing the return value of avpriv_find_start_code() + * would incorrectly imply that the start code is invalid (since the returned value + * equals <b>@c end </b>). + * + * @param[in] start_code The start code to test. + * @return A boolean that is true if and only if <b>@p start_code</b> is valid + */ +static av_always_inline int start_code_is_valid(uint32_t start_code) { + return (start_code & 0xFFFFFF00) == 0x100; +} + const uint8_t *avpriv_find_start_code(const uint8_t *p, const uint8_t *end, uint32_t *state); diff --git a/libavcodec/vaapi_vc1.c b/libavcodec/vaapi_vc1.c index d82336a3b3..33de4a63c8 100644 --- a/libavcodec/vaapi_vc1.c +++ b/libavcodec/vaapi_vc1.c @@ -473,7 +473,7 @@ static int vaapi_vc1_decode_slice(AVCodecContext *avctx, const uint8_t *buffer, int err; /* Current bit buffer is beyond any marker for VC-1, so skip it */ - if (avctx->codec_id == AV_CODEC_ID_VC1 && IS_MARKER(AV_RB32(buffer))) { + if (avctx->codec_id == AV_CODEC_ID_VC1 && start_code_is_valid(AV_RB32(buffer))) { buffer += 4; size -= 4; } diff --git a/libavcodec/vc1_common.h b/libavcodec/vc1_common.h index c0f0c8c2eb..8ff9802a51 100644 --- a/libavcodec/vc1_common.h +++ b/libavcodec/vc1_common.h @@ -41,8 +41,6 @@ enum VC1Code { }; //@} -#define IS_MARKER(x) (((x) & ~0xFF) == VC1_CODE_RES0) - /** Available Profiles */ //@{ enum Profile { @@ -61,7 +59,7 @@ static av_always_inline const uint8_t* find_next_marker(const uint8_t *src, cons if (end - src >= 4) { uint32_t mrk = 0xFFFFFFFF; src = avpriv_find_start_code(src, end, &mrk); - if (IS_MARKER(mrk)) + if (start_code_is_valid(mrk)) return src - 4; } return end; diff --git a/libavcodec/vc1dec.c b/libavcodec/vc1dec.c index 9f32e82f9e..d98c15f2e4 100644 --- a/libavcodec/vc1dec.c +++ b/libavcodec/vc1dec.c @@ -667,7 +667,7 @@ static int vc1_decode_frame(AVCodecContext *avctx, AVFrame *pict, if (!buf2) return AVERROR(ENOMEM); - if (IS_MARKER(AV_RB32(buf))) { /* frame starts with marker and needs to be parsed */ + if (start_code_is_valid(AV_RB32(buf))) { /* frame starts with marker and needs to be parsed */ const uint8_t *start, *end, *next; int size; diff --git a/libavformat/avs2dec.c b/libavformat/avs2dec.c index 0d5b23b65e..a5a7cee7d0 100644 --- a/libavformat/avs2dec.c +++ b/libavformat/avs2dec.c @@ -42,8 +42,8 @@ static int avs2_probe(const AVProbeData *p) while (ptr < end) { ptr = avpriv_find_start_code(ptr, end, &code); - state = code & 0xFF; - if ((code & 0xffffff00) == 0x100) { + if (start_code_is_valid(code)) { + state = code & 0xFF; if (AVS2_ISUNIT(state)) { if (sqb && !hds) { hds = ptr - sqb; diff --git a/libavformat/avs3dec.c b/libavformat/avs3dec.c index 2395df171b..112b28efa8 100644 --- a/libavformat/avs3dec.c +++ b/libavformat/avs3dec.c @@ -36,8 +36,8 @@ static int avs3video_probe(const AVProbeData *p) while (ptr < end) { ptr = avpriv_find_start_code(ptr, end, &code); - state = code & 0xFF; - if ((code & 0xFFFFFF00) == 0x100) { + if (start_code_is_valid(code)) { + state = code & 0xFF; if (state < AVS3_SEQ_START_CODE) { if (code < slice_pos) return 0; diff --git a/libavformat/cavsvideodec.c b/libavformat/cavsvideodec.c index b89851fbbb..398f1192dd 100644 --- a/libavformat/cavsvideodec.c +++ b/libavformat/cavsvideodec.c @@ -39,7 +39,7 @@ static int cavsvideo_probe(const AVProbeData *p) while (ptr < end) { ptr = avpriv_find_start_code(ptr, end, &code); - if ((code & 0xffffff00) == 0x100) { + if (start_code_is_valid(code)) { if(code < CAVS_SEQ_START_CODE) { /* slices have to be consecutive */ if(code < slice_pos) diff --git a/libavformat/mpegvideodec.c b/libavformat/mpegvideodec.c index 33c5d79794..88966af72a 100644 --- a/libavformat/mpegvideodec.c +++ b/libavformat/mpegvideodec.c @@ -44,7 +44,7 @@ static int mpegvideo_probe(const AVProbeData *p) while (ptr < end) { ptr = avpriv_find_start_code(ptr, end, &code); - if ((code & 0xffffff00) == 0x100) { + if (start_code_is_valid(code)) { switch(code){ case SEQ_START_CODE: if (!(ptr[3 + 1 + 2] & 0x20)) diff --git a/libavformat/rtpenc_mpv.c b/libavformat/rtpenc_mpv.c index c18c75082f..8b6987b7f2 100644 --- a/libavformat/rtpenc_mpv.c +++ b/libavformat/rtpenc_mpv.c @@ -57,7 +57,7 @@ void ff_rtp_send_mpegvideo(AVFormatContext *s1, const uint8_t *buf1, int size) while (1) { start_code = -1; r = avpriv_find_start_code(r1, end, &start_code); - if((start_code & 0xFFFFFF00) == 0x100) { + if (start_code_is_valid(start_code)) { /* New start code found */ if (start_code == 0x100) { frame_type = (r[1] & 0x38) >> 3; -- 2.34.1 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".