Reviewed-by: Reimar

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

The problem is that the argument 'q' is of the type uint8_t.
According to the JPEG standard, if 1 <= q <= 50, the scale factor
'S' should be 5000 / Q. Because the create_default_qtables() reuses
the variable 'q' to store the result of this calculation, for small
values of q < 19, q wil subsequently overflow and give wrong results
in the calculated quantization tables.

Instead, use a new variable 'S' (same name as in RFC2435) with the
proper range to store the result of the division.

Signed-off-by: Martin Storsjö <martin@martin.st>

Signed-off-by: Paul B Mahol <onemda@gmail.com>

This silences missing EOC marker when decoding j2k files with Psot set to 0.

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Helps in decoupling this code from mpegvideo.

It will be needed to initialize BlockDSP in the next commit.

Helps in decoupling this code from mpegvideo.

The size of the block is fixed (8x8 plus padding).

Helps in decoupling this code from mpegvideo.

Helps in decoupling this code from mpegvideo.

Use it instead of the embedded mpegvideo one. Update init function
signature to load it directly from the callers.

These buffers are just a way to store frame pointers and be able to
modify them without touching the original ones.

The two dependent decoders (WMV2 and VC1) do not need special care for
these fields: the former does not seem to use the dest buffers, while
the latter reinits them every time to the current frame data buffers.

So only keep a local copy rather than the one from mpegvideo.

27ms to 26ms with UHD 2160 input.

The test uses printf.

CC: libav-stable@libav.org

Signed-off-by: James Almer <jamrial@gmail.com>

Signed-off-by: James Almer <jamrial@gmail.com>

Reviewed-by: maintainer
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

- Added tests for av_find_info_tag().
    - Added test for av_get_known_color_name()

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

This is already taken care of by CLEANSUFFIXES.

Original mail and my own followup on ffmpeg-user earlier today:

I have a device sending out a MJPEG/RTP stream on a low quality setting.
Decoding and displaying the video with libavformat results in a washed
out, low contrast, greyish image. Playing the same stream with VLC results
in proper color representation.

Screenshots for comparison:

  http://zevv.nl/div/libav/shot-ffplay.jpg
  http://zevv.nl/div/libav/shot-vlc.jpg

A pcap capture of a few seconds of video and SDP file for playing the
stream are available at

  http://zevv.nl/div/libav/mjpeg.pcap
  http://zevv.nl/div/libav/mjpeg.sdp

I believe the problem might be in the calculation of the quantization
tables in the function create_default_qtables(), the attached patch
solves the issue for me.

The problem is that the argument 'q' is of the type uint8_t. According to the
JPEG standard, if 1 <= q <= 50, the scale factor 'S' should be 5000 / Q.
Because the create_default_qtables() reuses the variable 'q' to store the
result of this calculation, for small values of q < 19, q wil subsequently
overflow and give wrong results in the calculated quantization tables. The
patch below uses a new variable 'S' (same name as in RFC2435) with the proper
range to store the result of the division.

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Everything except ORing the sign is now done in the LUT.

Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Simplifies code

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Martin Storsjö <martin@martin.st>

Apply the default value for timeout in code instead of via the
avoption, to allow distinguishing the default value from the user
not setting anything at all.

Signed-off-by: Martin Storsjö <martin@martin.st>

Since all URLContexts have the same AVOptions, such AVOptions
will be applied on the outermost context only and removed from the
dict, while they probably make sense on all contexts.

This makes sure that rw_timeout gets propagated to the innermost
URLContext (to make sure it gets passed to the tcp protocol, when
opening a http connection for instance).

Alternatively, such matching options would be kept in the dict
and only removed after the ffurl_connect call.

Signed-off-by: Martin Storsjö <martin@martin.st>

This includes documentation and other modifications by
Lukasz Marek and Martin Storsjö.

Signed-off-by: Martin Storsjö <martin@martin.st>

Also add const to pointers in static functions within opt.c where
possible/necessary.

Signed-off-by: Martin Storsjö <martin@martin.st>

Using this requires setting the rw_timeout option to make it
terminate, alternatively using the interrupt callback (if used via
the API).

Signed-off-by: Martin Storsjö <martin@martin.st>

If set non-zero, this limits duration of the retry_transfer_wrapper()
loop, thus affecting ffurl_read*(), ffurl_write(). As soon as
one single byte is successfully received/transmitted, the timer
restarts.

This has further changes by Michael Niedermayer and Martin Storsjö.

Signed-off-by: Martin Storsjö <martin@martin.st>

Currently the list of avoptions for URLContext is empty though,
but such options will be added.

Signed-off-by: Martin Storsjö <martin@martin.st>

All tests were in the main method which produces a long main. Now, each test
is in his own method.

I think this produces a more clear code and follows more with the main
priority of FFmpeg "simplicity and small code size"

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

No new reference samples are needed for this as the file already exists
for testing the bitstream filter

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Anton Khirnov <anton@khirnov.net>

Signed-off-by: Anton Khirnov <anton@khirnov.net>