[FFmpeg-soc] [PATCH] AMR-WB Decoder

[Marcelo Galvão Póvoa]

On 11 September 2010 18:54, Vitor Sessak <vitor1001 at gmail.com> wrote:
> On 09/11/2010 06:08 PM, Marcelo Galvão Póvoa wrote:
>>
>> 2010/9/11 Marcelo Galvão Póvoa<marspeoplester at gmail.com>:
>>>
>>> On 11 September 2010 12:37, Vitor Sessak<vitor1001 at gmail.com>  wrote:
>>>>
>>>> On 09/11/2010 04:47 PM, Marcelo Galvão Póvoa wrote:
>>>>>
>>>>> On 9 September 2010 16:11, Vitor Sessak<vitor1001 at gmail.com>    wrote:
>>>>>>
>>>>>> On 09/07/2010 02:05 AM, Marcelo Galvão Póvoa wrote:
>>>>>>>
>>>>>>> On 6 September 2010 11:31, Vitor Sessak<vitor1001 at gmail.com>
>>>>>>>  wrote:
>>>>>>>>
>>>>>>>> On 09/06/2010 02:46 AM, Marcelo Galvăo Póvoa wrote:
>>>>>>>>>
>>>>
>>>> [...]
>>>>
>>>>>>>> Can celp_filters.c:ff_celp_circ_addf() simplify this?
>>>>>>>>
>>>>>>>
>>>>>>> I already gave some thought to that but I couldn't figure out how to
>>>>>>> use ff_celp_circ_addf() there. I wrote the algorithm the simplest way
>>>>>>> I could think of.
>>>>>>
>>>>>> Try
>>>>>>
>>>>>>        for (i = 0; i<    AMRWB_SFR_SIZE; i++)
>>>>>>            if (fixed_vector[i])
>>>>>>                ff_celp_circ_addf(buf, buf, coef, i, fixed_vector[i],
>>>>>>                                  AMRWB_SFR_SIZE);
>>>>>>
>>>>>>
>>>>>
>>>>> That's right indeed, thanks!
>>>>
>>>>> /*
>>>>>  * AMR wideband decoder
>>>>>  * Copyright (c) 2010 Marcelo Galvao Povoa
>>>>>  *
>>>>>  * This file is part of FFmpeg.
>>>>>  *
>>>>>  * FFmpeg is free software; you can redistribute it and/or
>>>>>  * modify it under the terms of the GNU Lesser General Public
>>>>>  * License as published by the Free Software Foundation; either
>>>>>  * version 2.1 of the License, or (at your option) any later version.
>>>>>  *
>>>>>  * FFmpeg is distributed in the hope that it will be useful,
>>>>>  * but WITHOUT ANY WARRANTY; without even the implied warranty of
>>>>>  * MERCHANTABILITY or FITNESS FOR A particular PURPOSE.  See the GNU
>>>>>  * Lesser General Public License for more details.
>>>>>  *
>>>>>  * You should have received a copy of the GNU Lesser General Public
>>>>>  * License along with FFmpeg; if not, write to the Free Software
>>>>>  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
>>>>> 02110-1301 USA
>>>>>  */
>>>>>
>>>>> #include "libavutil/lfg.h"
>>>>>
>>>>> #include "avcodec.h"
>>>>> #include "get_bits.h"
>>>>> #include "lsp.h"
>>>>> #include "celp_math.h"
>>>>> #include "celp_filters.h"
>>>>> #include "acelp_filters.h"
>>>>> #include "acelp_vectors.h"
>>>>> #include "acelp_pitch_delay.h"
>>>>>
>>>>> #include "amrwbdata.h"
>>>>
>>>> No need to include amr.h?
>>>>
>>>
>>> Oops, fixed
>>>
>>
>> Sorry, I forgot to define the table type before the include. Fixed
>
> Just one last think I just saw:
>
>
>>    ctx->fr_cur_mode = unpack_bitstream(ctx, buf, buf_size);
>>    expected_fr_size = ((cf_sizes_wb[ctx->fr_cur_mode] + 7) >> 3) + 1;
>>
>>    if (buf_size < expected_fr_size) {
>>        av_log(avctx, AV_LOG_ERROR,
>>            "Frame too small (%d bytes). Truncated file?\n", buf_size);
>>        *data_size = 0;
>>        return buf_size;
>>    }
>
> This check is not useful like that. Imagine that buf_size == 1. Then,
> unpack_bitstream will try to read buf[2] and will segfault. This check
> should be done before the call of ff_amr_bit_reorder().
>

I thought about that, but how I would calculate expected_fr_size if I
don't know of which mode the frame is? One solution would be doing
this check inside ff_amr_bit_reorder() just after decoding the header.

-- 
Marcelo