From b1e451f0e19a5ca56498a1458532ffb31296615d Mon Sep 17 00:00:00 2001 From: Vsevolod Stakhov Date: Wed, 27 May 2020 16:06:57 +0100 Subject: [PATCH] [Minor] Do not try to unpack streams with Predictor attribute --- lualib/lua_content/pdf.lua | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/lualib/lua_content/pdf.lua b/lualib/lua_content/pdf.lua index 57968013f..785959dfe 100644 --- a/lualib/lua_content/pdf.lua +++ b/lualib/lua_content/pdf.lua @@ -391,7 +391,7 @@ local function apply_pdf_filter(input, filt) end -- Conditionally apply a pipeline of stream filters and return uncompressed data -local function maybe_apply_filter(dict, data) +local function maybe_apply_filter(dict, data, pdf, task) local uncompressed = data if dict.Filter then @@ -400,6 +400,16 @@ local function maybe_apply_filter(dict, data) filt = {filt} end + if dict.DecodeParms then + local decode_params = maybe_dereference_object(dict.DecodeParms, pdf, task) + + if type(decode_params) == 'table' then + if decode_params.Predictor then + return nil,'predictor exists' + end + end + end + for _,f in ipairs(filt) do uncompressed = apply_pdf_filter(uncompressed, f) @@ -407,7 +417,7 @@ local function maybe_apply_filter(dict, data) end end - return uncompressed + return uncompressed,nil end -- Conditionally extract stream data from object and attach it as obj.uncompressed @@ -422,7 +432,7 @@ local function maybe_extract_object_stream(obj, pdf, task) tonumber(maybe_dereference_object(dict.Length, pdf, task)) or 0) local real_stream = obj.stream.data:span(1, len) - local uncompressed = maybe_apply_filter(dict, real_stream) + local uncompressed,filter_err = maybe_apply_filter(dict, real_stream, pdf, task) if uncompressed then obj.uncompressed = uncompressed @@ -430,8 +440,8 @@ local function maybe_extract_object_stream(obj, pdf, task) obj.major, obj.minor, len, uncompressed:len()) return obj.uncompressed else - lua_util.debugm(N, task, 'cannot extract object %s:%s; len = %s; filter = %s', - obj.major, obj.minor, len, dict.Filter) + lua_util.debugm(N, task, 'cannot extract object %s:%s; len = %s; filter = %s: %s', + obj.major, obj.minor, len, dict.Filter, filter_err) end end end -- 2.39.5