From 1e002b602f32008862ad113773e308c603ddf4bf Mon Sep 17 00:00:00 2001 From: Baptiste Coudurier Date: Sun, 26 Oct 2008 23:34:44 +0000 Subject: [PATCH] svq3 watermark decoding support, based on reverse engineering work by chrono Originally committed as revision 15718 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/svq3.c | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/libavcodec/svq3.c b/libavcodec/svq3.c index 67fa3172b46..0f7501b9ef8 100644 --- a/libavcodec/svq3.c +++ b/libavcodec/svq3.c @@ -703,6 +703,10 @@ static int svq3_decode_slice_header (H264Context *h) { s->gb.size_in_bits = h->next_slice_index - 8*(length - 1); skip_bits(&s->gb, 8); + if (h->svq3_watermark_key) { + uint32_t header = AV_RL32(&s->gb.buffer[(get_bits_count(&s->gb)>>3)+1]); + AV_WL32(&s->gb.buffer[(get_bits_count(&s->gb)>>3)+1], header ^ h->svq3_watermark_key); + } if (length > 0) { memcpy ((uint8_t *) &s->gb.buffer[get_bits_count(&s->gb) >> 3], &s->gb.buffer[s->gb.size_in_bits >> 3], (length - 1)); @@ -828,6 +832,38 @@ static int svq3_decode_frame (AVCodecContext *avctx, h->unknown_svq3_flag = get_bits1 (&gb); avctx->has_b_frames = !s->low_delay; + if (h->unknown_svq3_flag) { +#ifdef CONFIG_ZLIB + unsigned watermark_width = svq3_get_ue_golomb(&gb); + unsigned watermark_height = svq3_get_ue_golomb(&gb); + int u1 = svq3_get_ue_golomb(&gb); + int u2 = get_bits(&gb, 8); + int u3 = get_bits(&gb, 2); + int u4 = svq3_get_ue_golomb(&gb); + unsigned buf_len = watermark_width*watermark_height*4; + int offset = (get_bits_count(&gb)+7)>>3; + uint8_t *buf; + + if ((uint64_t)watermark_width*4 > UINT_MAX/watermark_height) + return -1; + + buf = av_malloc(buf_len); + av_log(avctx, AV_LOG_DEBUG, "watermark size: %dx%d\n", watermark_width, watermark_height); + av_log(avctx, AV_LOG_DEBUG, "u1: %x u2: %x u3: %x compressed data size: %d offset: %d\n", u1, u2, u3, u4, offset); + if (uncompress(buf, (uLong*)&buf_len, extradata + 8 + offset, size - offset) != Z_OK) { + av_log(avctx, AV_LOG_ERROR, "could not uncompress watermark logo\n"); + av_free(buf); + return -1; + } + h->svq3_watermark_key = ff_svq1_packet_checksum(buf, buf_len, 0); + h->svq3_watermark_key = h->svq3_watermark_key << 16 | h->svq3_watermark_key; + av_log(avctx, AV_LOG_DEBUG, "watermark key %#x\n", h->svq3_watermark_key); + av_free(buf); +#else + av_log(avctx, AV_LOG_ERROR, "this svq3 file contains watermark which need zlib support compiled in\n"); + return -1; +#endif + } } } -- 2.39.2