From: Wu Jianhua <toq...@outlook.com> Signed-off-by: Wu Jianhua <toq...@outlook.com> --- libavcodec/h274.c | 163 ++++++++++++++++++++++++++++++++++++++++++++++ libavcodec/h274.h | 7 ++ 2 files changed, 170 insertions(+)
diff --git a/libavcodec/h274.c b/libavcodec/h274.c index 5709200322..9edc705042 100644 --- a/libavcodec/h274.c +++ b/libavcodec/h274.c @@ -26,7 +26,11 @@ */ #include "libavutil/avassert.h" +#include "libavutil/bswap.h" +#include "libavutil/crc.h" #include "libavutil/imgutils.h" +#include "libavutil/md5.h" +#include "libavutil/mem.h" #include "h274.h" @@ -790,3 +794,162 @@ static const int8_t R64T[64][64] = { 17, -16, 15, -14, 13, -12, 11, -10, 9, -8, 7, -6, 4, -3, 2, -1, } }; + +static int verify_plane_md5(struct AVMD5 *ctx, + const uint8_t *src, const int w, const int h, const int stride, + const uint8_t *expected) +{ +#define MD5_SIZE 16 + uint8_t md5[MD5_SIZE]; + av_md5_init(ctx); + for (int j = 0; j < h; j++) { + av_md5_update(ctx, src, w); + src += stride; + } + av_md5_final(ctx, md5); + + if (memcmp(md5, expected, MD5_SIZE)) + return AVERROR_INVALIDDATA; + + return 0; +} + +static int verify_plane_crc(const uint8_t *src, const int w, const int h, const int stride, + const uint8_t *expected) +{ + uint32_t crc = 0x0F1D; // CRC-16-CCITT-AUG + const AVCRC *ctx = av_crc_get_table(AV_CRC_16_CCITT); + + for (int j = 0; j < h; j++) { + crc = av_crc(ctx, crc, src, w); + src += stride; + } + crc = av_bswap16(crc); + + if (memcmp(&crc, expected, sizeof(uint16_t))) + return AVERROR_INVALIDDATA; + + return 0; +} + +#define CAL_CHECKSUM(pixel) (checksum + ((pixel) ^ xor_mask)) +static int verify_plane_checksum(const uint8_t *src, const int w, const int h, const int stride, const int ps, + const uint8_t *expected) +{ + uint32_t checksum = 0; + + for (int y = 0; y < h; y++) { + for (int x = 0; x < w; x++) { + const int xor_mask = (x & 0xFF) ^ (y & 0xFF) ^ (x >> 8) ^ (y >> 8); + checksum = CAL_CHECKSUM(src[x << ps]); + if (ps) + checksum = CAL_CHECKSUM(src[(x << ps) + 1]); + } + src += stride; + } + + if (checksum != *(uint32_t*)expected) + return AVERROR_INVALIDDATA; + + return 0; +} + +static const uint8_t *get_plane_hash(const H274SEIPictureHash *h, const int plane) +{ + if (!h->hash_type) + return h->md5[plane]; + if (h->hash_type == 1) + return (uint8_t*)&h->crc[plane]; + return (uint8_t*)&h->checksum[plane]; +} + +enum { + HASH_MD5SUM, + HASH_CRC, + HASH_CHECKSUM, + HASH_LAST = HASH_CHECKSUM, +}; + +struct H274HashContext { + int type; + struct AVMD5 *ctx; +}; + +int ff_h274_hash_freep(H274HashContext **ctx) +{ + if (ctx && *ctx) { + H274HashContext *c = *ctx; + if (c->ctx) + av_free(c->ctx); + av_freep(ctx); + } + return 0; +} + +int ff_h274_hash_init(H274HashContext **ctx, const int type) +{ + H274HashContext *c; + + if (type > HASH_LAST || !ctx) + return AVERROR(EINVAL); + + c = *ctx; + if (c) { + if (c->type != type) { + if (c->type == HASH_MD5SUM) + av_freep(&c->ctx); + c->type = type; + } + } else { + *ctx = c = av_mallocz(sizeof(H274HashContext)); + if (!c) + return AVERROR(ENOMEM); + c->type = type; + } + + if (type == HASH_MD5SUM && !c->ctx) { + c->ctx = av_md5_alloc(); + if (!c->ctx) + return AVERROR(ENOMEM); + } + + return 0; +} + +int ff_h274_hash_verify(H274HashContext *c, const H274SEIPictureHash *hash, + const AVFrame *frame, const int coded_width, const int coded_height) +{ + const AVPixFmtDescriptor *desc; + int err = 0; + + if (!c || !hash || !frame) + return AVERROR(EINVAL); + + if (c->type != hash->hash_type) + return AVERROR(EINVAL); + + desc = av_pix_fmt_desc_get(frame->format); + if (!desc) + return AVERROR(EINVAL); + + for (int i = 0; i < desc->nb_components; i++) { + const int w = i ? (coded_width >> desc->log2_chroma_w) : coded_width; + const int h = i ? (coded_height >> desc->log2_chroma_h) : coded_height; + const int ps = desc->comp[i].step - 1; + const uint8_t *expected = get_plane_hash(hash, i); + const uint8_t *src = frame->data[i]; + const int stride = frame->linesize[i]; + + if (c->type == HASH_MD5SUM) + err = verify_plane_md5(c->ctx, src, w << ps, h, stride, expected); + else if (c->type == HASH_CRC) + err = verify_plane_crc(src, w << ps, h, stride, expected); + else if (c->type == HASH_CHECKSUM) + err = verify_plane_checksum(src, w, h, stride, ps, expected); + if (err < 0) + goto fail; + } + +fail: + return err; +} diff --git a/libavcodec/h274.h b/libavcodec/h274.h index e1803edaf3..e2bb1aec55 100644 --- a/libavcodec/h274.h +++ b/libavcodec/h274.h @@ -64,6 +64,8 @@ int ff_h274_apply_film_grain(AVFrame *out, const AVFrame *in, H274FilmGrainDatabase *db, const AVFilmGrainParams *params); +typedef struct H274HashContext H274HashContext; + typedef struct H274SEIPictureHash { int present; union { @@ -74,4 +76,9 @@ typedef struct H274SEIPictureHash { uint8_t hash_type; } H274SEIPictureHash; +int ff_h274_hash_init(H274HashContext **c, int type); +int ff_h274_hash_verify(H274HashContext *c, const H274SEIPictureHash *hash, + const AVFrame *frame, int coded_width, int coded_height); +int ff_h274_hash_freep(H274HashContext **c); + #endif /* AVCODEC_H274_H */ -- 2.44.0.windows.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".