[FFmpeg-devel] [PATCH v5] lavc/rawdec: Use AV_PIX_FMT_PAL8 for 1-bit raw AVI video, and more
Mats Peterson
matsp888 at yahoo.com
Mon Jan 25 01:23:00 CET 2016
On 01/25/2016 01:14 AM, Michael Niedermayer wrote:
> On Fri, Jan 22, 2016 at 03:44:30PM +0100, Mats Peterson wrote:
>> You'll have to excuse me, Michael, but the changes I've made,
>> including the line alignment changes, are dependent on each other,
>> and not easy or very logical to split. Here's a new version that
>> displays the Matrix video correctly.
>>
>> Mats
>>
>> --
>> Mats Peterson
>> http://matsp888.no-ip.org/~mats/
>
>> raw.c | 2 -
>> rawdec.c | 92 +++++++++++++++++++++++++++++++++++++++++----------------------
>> 2 files changed, 62 insertions(+), 32 deletions(-)
>> 7e3ead59067fc542c5ad6c3231ab5783bad57c0b 0001-lavc-rawdec-Use-AV_PIX_FMT_PAL8-for-1-bit-raw-AVI-vi.patch
>> From 0f99c5bdcf39230556eef82fa849dd6342208539 Mon Sep 17 00:00:00 2001
>> From: Mats Peterson <matsp888 at yahoo.com>
>> Date: Fri, 22 Jan 2016 15:38:26 +0100
>> Subject: [PATCH v5] lavc/rawdec: Use AV_PIX_FMT_PAL8 for 1-bit raw AVI video, and more
>>
>> The stuff about 1-bit video not necessarily being black & white in
>> QuickTime goes for AVI as well. Being 1 bit per pixel only means that
>> the data is bi-level. The two colors can be any color. Since many
>> 1 bpp AVI files don't have a palette following the BITMAPINFOHEADER,
>> I'm setting a "default" black & white palette in raw_init_decoder().
>>
>> Also, the line alignment for 4 bpp and 8 bpp depths generated warning
>> messages. The line alignment is now 16 bytes for 1, 2, 4, and 8 bpp depth.
>>
>> Mats
>>
>> ---
>> libavcodec/raw.c | 2 +-
>> libavcodec/rawdec.c | 92 ++++++++++++++++++++++++++++++++++-----------------
>> 2 files changed, 62 insertions(+), 32 deletions(-)
>>
>> diff --git a/libavcodec/raw.c b/libavcodec/raw.c
>> index 3f2cc11..3979c5c 100644
>> --- a/libavcodec/raw.c
>> +++ b/libavcodec/raw.c
>> @@ -242,7 +242,7 @@ unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat fmt)
>> }
>>
>> const PixelFormatTag avpriv_pix_fmt_bps_avi[] = {
>> - { AV_PIX_FMT_MONOWHITE, 1 },
>> + { AV_PIX_FMT_PAL8, 1 },
>> { AV_PIX_FMT_PAL8, 2 },
>> { AV_PIX_FMT_PAL8, 4 },
>> { AV_PIX_FMT_PAL8, 8 },
>> diff --git a/libavcodec/rawdec.c b/libavcodec/rawdec.c
>> index cb0364c..9c4e69a 100644
>> --- a/libavcodec/rawdec.c
>> +++ b/libavcodec/rawdec.c
>> @@ -41,7 +41,7 @@ typedef struct RawVideoContext {
>> AVBufferRef *palette;
>> int frame_size; /* size of the frame in bytes */
>> int flip;
>> - int is_1_2_4_bpp; // 1 bpp raw in mov, and 2 or 4 bpp raw in avi/mov
>> + int is_1_2_4_8_bpp; // 1, 2, 4 and 8 bpp raw in avi/mov
>> int is_yuv2;
>> int is_lt_16bpp; // 16bpp pixfmt and bits_per_coded_sample < 16
>> int tff;
>> @@ -94,8 +94,11 @@ static av_cold int raw_init_decoder(AVCodecContext *avctx)
>> return AVERROR(ENOMEM);
>> if (desc->flags & AV_PIX_FMT_FLAG_PSEUDOPAL)
>> avpriv_set_systematic_pal2((uint32_t*)context->palette->data, avctx->pix_fmt);
>> - else
>> + else {
>> memset(context->palette->data, 0, AVPALETTE_SIZE);
>> + if (avctx->bits_per_coded_sample == 1)
>> + memset(context->palette->data, 0xff, 4);
>> + }
>> }
>>
>> if ((avctx->extradata_size >= 9 &&
>> @@ -153,19 +156,20 @@ static int raw_decode(AVCodecContext *avctx, void *data, int *got_frame,
>> RawVideoContext *context = avctx->priv_data;
>> const uint8_t *buf = avpkt->data;
>> int buf_size = avpkt->size;
>> + int avpkt_stride = avpkt->size / avctx->height;
>> int linesize_align = 4;
>> int res, len;
>> int need_copy;
>>
>> AVFrame *frame = data;
>>
>> - if ((avctx->bits_per_coded_sample == 4 || avctx->bits_per_coded_sample == 2
>> - || avctx->bits_per_coded_sample == 1) &&
>> + if ((avctx->bits_per_coded_sample == 8 || avctx->bits_per_coded_sample == 4
>> + || avctx->bits_per_coded_sample == 2 || avctx->bits_per_coded_sample == 1) &&
>> avctx->pix_fmt == AV_PIX_FMT_PAL8 &&
>> (!avctx->codec_tag || avctx->codec_tag == MKTAG('r','a','w',' '))) {
>> - context->is_1_2_4_bpp = 1;
>> + context->is_1_2_4_8_bpp = 1;
>> context->frame_size = av_image_get_buffer_size(avctx->pix_fmt,
>> - FFALIGN(avctx->width, 32),
>> + FFALIGN(avctx->width, 16),
>> avctx->height, 1);
>> } else {
>> context->is_lt_16bpp = av_get_bits_per_pixel(desc) == 16 && avctx->bits_per_coded_sample && avctx->bits_per_coded_sample < 16;
>> @@ -175,7 +179,7 @@ static int raw_decode(AVCodecContext *avctx, void *data, int *got_frame,
>> if (context->frame_size < 0)
>> return context->frame_size;
>>
>> - need_copy = !avpkt->buf || context->is_1_2_4_bpp || context->is_yuv2 || context->is_lt_16bpp;
>> + need_copy = !avpkt->buf || context->is_1_2_4_8_bpp || context->is_yuv2 || context->is_lt_16bpp;
>>
>> frame->pict_type = AV_PICTURE_TYPE_I;
>> frame->key_frame = 1;
>> @@ -202,39 +206,65 @@ static int raw_decode(AVCodecContext *avctx, void *data, int *got_frame,
>> if (!frame->buf[0])
>> return AVERROR(ENOMEM);
>>
>> - // 1 bpp raw in mov, and 2 or 4 bpp raw in avi/mov
>> - if (context->is_1_2_4_bpp) {
>> - int i;
>> + // 1, 2, 4 and 8 bpp raw in avi/mov
>> + if (context->is_1_2_4_8_bpp) {
>> + int i, j, row_pix = 0;
>> uint8_t *dst = frame->buf[0]->data;
>> buf_size = context->frame_size - AVPALETTE_SIZE;
>> - if (avctx->bits_per_coded_sample == 4) {
>> - for (i = 0; 2 * i + 1 < buf_size && i<avpkt->size; i++) {
>> - dst[2 * i + 0] = buf[i] >> 4;
>> - dst[2 * i + 1] = buf[i] & 15;
>> + if (avctx->bits_per_coded_sample == 8) {
>> + for (i = 0, j = 0; j < buf_size && i<avpkt->size; i++, j++) {
>> + dst[j] = buf[i];
>> + row_pix++;
>> + if (row_pix == avctx->width) {
>> + i += avpkt_stride - (i % avpkt_stride) - 1;
>> + j += 16 - (j % 16) - 1;
>> + row_pix = 0;
>> + }
>> + }
>> + } else if (avctx->bits_per_coded_sample == 4) {
>> + for (i = 0, j = 0; 2 * j + 1 < buf_size && i<avpkt->size; i++, j++) {
>> + dst[2 * j + 0] = buf[i] >> 4;
>> + dst[2 * j + 1] = buf[i] & 15;
>> + row_pix += 2;
>> + if (row_pix >= avctx->width) {
>> + i += avpkt_stride - (i % avpkt_stride) - 1;
>> + j += 8 - (j % 8) - 1;
>> + row_pix = 0;
>> + }
>> }
>> - linesize_align = 8;
>
> decreasing linesize_align below the SIMD register size is undesirable
> as it could lead to unaligned accesses in subsequent code using
> the frames which would cause speedloss
>
>
I haven't decreased anything, rather increased it from previous 4 and
8-byte line alignments to 16 bytes. Or do you want me to use 32-byte
alignment? That's a lot of overhead. And please read your mail.
Mats
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