[FFmpeg-devel] [PATCH] avcodec: add ARBC decoder
James Almer
jamrial at gmail.com
Tue Jan 22 16:03:11 EET 2019
On 1/22/2019 10:30 AM, Paul B Mahol wrote:
> On 1/22/19, James Almer <jamrial at gmail.com> wrote:
>> On 1/22/2019 6:55 AM, Paul B Mahol wrote:
>>> Thanks Kostya for great help in reversing binary.
>>>
>>> Signed-off-by: Paul B Mahol <onemda at gmail.com>
>>> ---
>>> libavcodec/Makefile | 1 +
>>> libavcodec/allcodecs.c | 1 +
>>> libavcodec/arbc.c | 203 ++++++++++++++++++++++++++++++++++++++++
>>> libavcodec/avcodec.h | 1 +
>>> libavcodec/codec_desc.c | 7 ++
>>> libavformat/riff.c | 1 +
>>> 6 files changed, 214 insertions(+)
>>> create mode 100644 libavcodec/arbc.c
>>>
>>> diff --git a/libavcodec/Makefile b/libavcodec/Makefile
>>> index bf746c143d..8e240aecf0 100644
>>> --- a/libavcodec/Makefile
>>> +++ b/libavcodec/Makefile
>>> @@ -198,6 +198,7 @@ OBJS-$(CONFIG_APTX_HD_DECODER) += aptx.o
>>> OBJS-$(CONFIG_APTX_HD_ENCODER) += aptx.o
>>> OBJS-$(CONFIG_APNG_DECODER) += png.o pngdec.o pngdsp.o
>>> OBJS-$(CONFIG_APNG_ENCODER) += png.o pngenc.o
>>> +OBJS-$(CONFIG_ARBC_DECODER) += arbc.o
>>> OBJS-$(CONFIG_SSA_DECODER) += assdec.o ass.o
>>> OBJS-$(CONFIG_SSA_ENCODER) += assenc.o ass.o
>>> OBJS-$(CONFIG_ASS_DECODER) += assdec.o ass.o
>>> diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
>>> index fe0376e27e..5cbb09a5a4 100644
>>> --- a/libavcodec/allcodecs.c
>>> +++ b/libavcodec/allcodecs.c
>>> @@ -41,6 +41,7 @@ extern AVCodec ff_anm_decoder;
>>> extern AVCodec ff_ansi_decoder;
>>> extern AVCodec ff_apng_encoder;
>>> extern AVCodec ff_apng_decoder;
>>> +extern AVCodec ff_arbc_decoder;
>>> extern AVCodec ff_asv1_encoder;
>>> extern AVCodec ff_asv1_decoder;
>>> extern AVCodec ff_asv2_encoder;
>>> diff --git a/libavcodec/arbc.c b/libavcodec/arbc.c
>>> new file mode 100644
>>> index 0000000000..59a1d7bf0a
>>> --- /dev/null
>>> +++ b/libavcodec/arbc.c
>>> @@ -0,0 +1,203 @@
>>> +/*
>>> + * Gryphon's Anim Compressor decoder
>>> + * Copyright (c) 2018 Paul B Mahol
>>> + *
>>> + * 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 <stdio.h>
>>> +#include <stdlib.h>
>>> +#include <string.h>
>>> +
>>> +#include "libavutil/imgutils.h"
>>> +#include "libavutil/internal.h"
>>> +#include "libavutil/intreadwrite.h"
>>> +#include "libavutil/mem.h"
>>> +
>>> +#include "avcodec.h"
>>> +#include "bytestream.h"
>>> +#include "internal.h"
>>> +
>>> +typedef struct ARBCContext {
>>> + GetByteContext gb;
>>> +
>>> + AVFrame *prev_frame;
>>> +} ARBCContext;
>>> +
>>> +static void fill_tile4(AVCodecContext *avctx, uint8_t *color, AVFrame
>>> *frame)
>>> +{
>>> + ARBCContext *s = avctx->priv_data;
>>> + GetByteContext *gb = &s->gb;
>>> + int nb_tiles = bytestream2_get_le16(gb);
>>> + int h = avctx->height - 1;
>>> +
>>> + for (int i = 0; i < nb_tiles; i++) {
>>> + int y = bytestream2_get_byte(gb);
>>> + int x = bytestream2_get_byte(gb);
>>> + uint16_t mask = bytestream2_get_le16(gb);
>>> + int start_y = y * 4, start_x = x * 4;
>>> + int end_y = start_y + 4, end_x = start_x + 4;
>>> +
>>> + for (int j = start_y; j < end_y; j++) {
>>> + for (int k = start_x; k < end_x; k++) {
>>> + if (mask & 0x8000) {
>>> + if (j >= avctx->height || k >= avctx->width)
>>> + continue;
>>> + frame->data[0][frame->linesize[0] * (h - j) + 3 * k +
>>> 0] = color[0];
>>> + frame->data[0][frame->linesize[0] * (h - j) + 3 * k +
>>> 1] = color[1];
>>> + frame->data[0][frame->linesize[0] * (h - j) + 3 * k +
>>> 2] = color[2];
>>> + }
>>> + mask = mask << 1;
>>
>> get_bits(). Same below.
>
> Oh, come one, I had enough of this nonsense.
> This is 16 bit number, using fucking get bits is overkill.
> Get over it.
Don't get pissy about nothing. I asked nothing that deserves that kind
of reaction.
Doing mask & 0x8000 then shifting it left by one at every loop is weird
and one of the reasons why get_bits was written for. But do however you
prefer.
>
>>
>>> + }
>>> + }
>>> + }
>>> +}
>>> +
>>> +static void fill_tileX(AVCodecContext *avctx, int tile_width, int
>>> tile_height,
>>> + uint8_t *color, AVFrame *frame)
>>> +{
>>> + ARBCContext *s = avctx->priv_data;
>>> + GetByteContext *gb = &s->gb;
>>> + const int step_h = tile_height / 4;
>>> + const int step_w = tile_width / 4;
>>> + int nb_tiles = bytestream2_get_le16(gb);
>>> + int h = avctx->height - 1;
>>> +
>>> + for (int i = 0; i < nb_tiles; i++) {
>>> + int y = bytestream2_get_byte(gb);
>>> + int x = bytestream2_get_byte(gb);
>>> + uint16_t mask = bytestream2_get_le16(gb);
>>> + int start_y = y * tile_height, start_x = x * tile_width;
>>> + int end_y = start_y + tile_height, end_x = start_x + tile_width;
>>> +
>>> + for (int j = start_y; j < end_y; j += step_h) {
>>> + for (int k = start_x; k < end_x; k += step_w) {
>>> + if (mask & 0x8000U) {
>>> + for (int m = 0; m < step_h; m++) {
>>> + for (int n = 0; n < step_w; n++) {
>>> + if (j + m >= avctx->height || k + n >=
>>> avctx->width)
>>> + continue;
>>> + frame->data[0][frame->linesize[0] * (h - (j +
>>> m)) + 3 * (k + n) + 0] = color[0];
>>> + frame->data[0][frame->linesize[0] * (h - (j +
>>> m)) + 3 * (k + n) + 1] = color[1];
>>> + frame->data[0][frame->linesize[0] * (h - (j +
>>> m)) + 3 * (k + n) + 2] = color[2];
>>> + }
>>> + }
>>> + }
>>> + mask = mask << 1;
>>> + }
>>> + }
>>> + }
>>> +}
>>> +
>>> +static int decode_frame(AVCodecContext *avctx, void *data,
>>> + int *got_frame, AVPacket *avpkt)
>>> +{
>>> + ARBCContext *s = avctx->priv_data;
>>> + AVFrame *const frame = data;
>>
>> No const.
>
> Will remove.
>
>>
>>> + int ret, nb_segments, keyframe = 1;
>>> +
>>> + if (avpkt->size < 1)
>>> + return AVERROR_INVALIDDATA;
>>> +
>>> + if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
>>> + return ret;
>>> +
>>> + if (s->prev_frame->data[0]) {
>>> + ret = av_frame_copy(frame, s->prev_frame);
>>> + if (ret < 0)
>>> + return ret;
>>> + }
>>> +
>>> + bytestream2_init(&s->gb, avpkt->data, avpkt->size);
>>> + bytestream2_skip(&s->gb, 8);
>>> + nb_segments = bytestream2_get_le16(&s->gb);
>>> + if (nb_segments == 0)
>>> + keyframe = 0;
>>> +
>>> + for (int i = 0; i < nb_segments; i++) {
>>> + int resolution_flag;
>>> + uint8_t fill[3];
>>> +
>>> + if (bytestream2_get_bytes_left(&s->gb) <= 0)
>>> + return AVERROR_INVALIDDATA;
>>> +
>>> + fill[0] = bytestream2_get_byte(&s->gb);
>>> + bytestream2_skip(&s->gb, 1);
>>> + fill[1] = bytestream2_get_byte(&s->gb);
>>> + bytestream2_skip(&s->gb, 1);
>>> + fill[2] = bytestream2_get_byte(&s->gb);
>>> + bytestream2_skip(&s->gb, 1);
>>> + resolution_flag = bytestream2_get_byte(&s->gb);
>>> +
>>> + if (resolution_flag & 0x10)
>>> + fill_tileX(avctx, 1024, 1024, fill, frame);
>>> + if (resolution_flag & 0x08)
>>> + fill_tileX(avctx, 256, 256, fill, frame);
>>> + if (resolution_flag & 0x04)
>>> + fill_tileX(avctx, 64, 64, fill, frame);
>>> + if (resolution_flag & 0x02)
>>> + fill_tileX(avctx, 16, 16, fill, frame);
>>> + if (resolution_flag & 0x01)
>>> + fill_tile4(avctx, fill, frame);
>>> + }
>>> +
>>> + av_frame_unref(s->prev_frame);
>>> + if ((ret = av_frame_ref(s->prev_frame, frame)) < 0)
>>> + return ret;
>>> +
>>> + frame->pict_type = keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
>>> + frame->key_frame = keyframe;
>>> + *got_frame = 1;
>>> +
>>> + return avpkt->size;
>>> +}
>>> +
>>> +static av_cold int decode_init(AVCodecContext *avctx)
>>> +{
>>> + ARBCContext *s = avctx->priv_data;
>>> +
>>> + avctx->pix_fmt = AV_PIX_FMT_RGB24;
>>> +
>>> + s->prev_frame = av_frame_alloc();
>>> + if (!s->prev_frame)
>>> + return AVERROR(ENOMEM);
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static av_cold int decode_close(AVCodecContext *avctx)
>>> +{
>>> + ARBCContext *s = avctx->priv_data;
>>> +
>>> + av_frame_free(&s->prev_frame);
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +AVCodec ff_arbc_decoder = {
>>> + .name = "arbc",
>>> + .long_name = NULL_IF_CONFIG_SMALL("Gryphon's Anim Compressor"),
>>> + .type = AVMEDIA_TYPE_VIDEO,
>>> + .id = AV_CODEC_ID_ARBC,
>>> + .priv_data_size = sizeof(ARBCContext),
>>> + .init = decode_init,
>>> + .decode = decode_frame,
>>> + .close = decode_close,
>>> + .capabilities = AV_CODEC_CAP_DR1,
>>> + .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
>>> + FF_CODEC_CAP_INIT_CLEANUP,
>>
>> No need for this one. Only s->prev_frame is allocated in init(), and if
>> that fails then close() would do nothing.
>
> What? Nonsense.
INIT_CLEANUP is a flag to tell avcodec_open2() to call AVCodec.close()
if AVCodec.init() fails. Since s->prev_frame is the only thing allocated
by init(), calling close() after that failed to allocate is pointless.
s->prev_frame will be NULL and close() will be essentially a nop.
>
>>
>> What's missing is AV_CODEC_CAP_DR1 seeing you use get_buffer.
>
> Sorry, but you are not making any sense here. DR1 is right above.
Right, missed it.
>
>>
>>> +};
>>> diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
>>> index 90f9f08289..72dc277dfd 100644
>>> --- a/libavcodec/avcodec.h
>>> +++ b/libavcodec/avcodec.h
>>> @@ -453,6 +453,7 @@ enum AVCodecID {
>>> AV_CODEC_ID_WCMV,
>>> AV_CODEC_ID_RASC,
>>> AV_CODEC_ID_HYMT,
>>> + AV_CODEC_ID_ARBC,
>>>
>>> /* various PCM "codecs" */
>>> AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at
>>> the start of audio codecs
>>> diff --git a/libavcodec/codec_desc.c b/libavcodec/codec_desc.c
>>> index 10a639101c..7b254c1d45 100644
>>> --- a/libavcodec/codec_desc.c
>>> +++ b/libavcodec/codec_desc.c
>>> @@ -1698,6 +1698,13 @@ static const AVCodecDescriptor codec_descriptors[]
>>> = {
>>> .long_name = NULL_IF_CONFIG_SMALL("HuffYUV MT"),
>>> .props = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSLESS,
>>> },
>>> + {
>>> + .id = AV_CODEC_ID_ARBC,
>>> + .type = AVMEDIA_TYPE_VIDEO,
>>> + .name = "arbc",
>>> + .long_name = NULL_IF_CONFIG_SMALL("Gryphon's Anim Compressor"),
>>> + .props = AV_CODEC_PROP_LOSSY,
>>> + },
>>>
>>> /* various PCM "codecs" */
>>> {
>>> diff --git a/libavformat/riff.c b/libavformat/riff.c
>>> index d5a509c8b9..8f0fd99e22 100644
>>> --- a/libavformat/riff.c
>>> +++ b/libavformat/riff.c
>>> @@ -476,6 +476,7 @@ const AVCodecTag ff_codec_bmp_tags[] = {
>>> { AV_CODEC_ID_WCMV, MKTAG('W', 'C', 'M', 'V') },
>>> { AV_CODEC_ID_RASC, MKTAG('R', 'A', 'S', 'C') },
>>> { AV_CODEC_ID_HYMT, MKTAG('H', 'Y', 'M', 'T') },
>>> + { AV_CODEC_ID_ARBC, MKTAG('A', 'R', 'B', 'C') },
>>> { AV_CODEC_ID_NONE, 0 }
>>> };
>>>
>>>
>>
>> _______________________________________________
>> ffmpeg-devel mailing list
>> ffmpeg-devel at ffmpeg.org
>> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>>
> _______________________________________________
> ffmpeg-devel mailing list
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> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
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